It is Time to Address Fear of Cancer Recurrence in Family Caregivers: Feasibility and Acceptability of a Randomized Pilot Study of the Family Caregiver Version of the Fear of Recurrence Therapy (FC‐FORT)

ABSTRACT

Objective

Fear of cancer recurrence (FCR) is common, persistent, and associated with lower quality of life, impaired functioning, and psychological distress in family caregivers (FC) of individuals with a cancer diagnosis. Interventions are needed to specifically target FCR in FC. This study aimed to pilot test the adapted Family Caregiver—Fear Of Recurrence Therapy (FC‐FORT) to establish its feasibility, acceptability, and clinical significance.

Methods

This pilot study used a mixed‐method, parallel, two‐group randomized control trial (FC‐FORT vs. waitlist control group) design. Women FC were recruited through Canadian hospitals, community partners, and social media. FC in the intervention group completed 7 weekly sessions of virtual group therapy (FC‐FORT) and an exit interview. All participants completed questionnaires at baseline, post‐intervention, and 3‐month follow‐up. Feasibility (e.g., recruitment, allocation, fidelity), acceptability (e.g., dropout, completion, satisfaction) and clinical significance of secondary outcomes were evaluated. Descriptive statistics, mixed ANOVAs, and conventional content analyses were used.

Results

Regarding feasibility, 22 FC were recruited, 18 were randomized and therapist fidelity was 87%. As to acceptability, 67% of participants completed $\ge$ 5 sessions (33% dropout). Questionnaire completion rate was 92%. FC satisfaction was 80%. Analyses did not reveal any significant differences on the secondary outcomes between groups. Qualitative analyses revealed high importance, helpfulness, satisfaction, and group cohesion. Suggestions were made by FC for improvements.

Conclusions

This is one of the first interventions to address FCR in FC. While acceptability of FC‐FORT was good, important feasibility issues need to be addressed before moving forward with a larger randomized control trial.

Trial Registration

NCT, NCT05441384. Registered July 1st, 2022, https://classic.clinicaltrials.gov/ct2/show/NCT05441384

1. Background

Fear of cancer recurrence (FCR) can be defined as the ‘fear, worry or concern that cancer may come back or progress’ [1]. Whereas FCR has been well documented in cancer survivors [2], less is known about family caregivers' (FC) experience of FCR. FC, defined as family members who provide unpaid and informal support, play an integral role in the treatment and care of individuals with a cancer diagnosis [3]. Recent systematic reviews [4, 5, 6] indicate that approximately 50% of FC experience levels of FCR equal or greater than those reported by cancer survivors. Similarly to survivors, FCR in FC is persistent, associated with lower quality of life (QoL), lower functioning, and higher psychological distress (i.e., depression, anxiety, loneliness) [4, 5, 6]. Furthermore, consistent positive associations have been found between levels of FCR in FC and survivors [4, 5]. Therefore, treating FCR in FC could improve QoL for both FC and cancer survivors. Qualitative differences [7, 8] and conceptual models [9] are emerging distinguishing the experience of FCR in FC from that of survivors. While shared themes like fear, uncertainty, hopelessness, and liminality exist, unique FC themes related to FCR include concerns about losing a loved one or witnessing their suffering, the caregiver's protective role, and feeling unprepared [7, 8].

Although there is evidence that interventions created to address FCR in cancer survivors are effective [10], to date, there have been few attempts [11, 12] to provide these treatments to FC despite their unmet FCR needs. The goal of the present study was to pilot test an adapted version of the validated in‐person group intervention for cancer survivors entitled the Fear Of Recurrence Therapy (FORT) [13, 14, 15]. In the project's initial phase, FORT (i.e., manuals, content, administration) was adapted to FC (adapted name: Family Caregiver—Fear Of Recurrence Therapy) with input from an advisory board, and its usability was evaluated [16]. Our adaptation accounted for the consistent evidence that FC often face barriers to accessing services (e.g., time, finances, negative perceptions of mental health services) [17, 18]. In addition, previous in‐person therapy studies show low attendance and high attrition rates [19] among FC. In combination with the impacts of COVID‐19, our adaptation aimed to mitigate these limitations by also adapting FORT to an online format.

The primary aims of this pilot randomized controlled trial (RCT) were to examine the feasibility, acceptability, and clinical significance of FC‐FORT. The results of this pilot study informed the relevance of a larger RCT.

2. Methods

2.1. Study Design

This study is a pilot, mixed‐method, parallel, two‐group randomized control trial where FC were randomized to receive either (1) FC‐FORT or (2) waitlist control group (WLCG). The primary outcomes were feasibility (e.g., recruitment, allocation, fidelity) and acceptability (e.g., dropout, completion, satisfaction). The secondary outcome investigated the potential clinical significance of FC‐FORT on various aspects (e.g., FCR, intolerance of uncertainty). See CONSORT diagram (Figure 1).

FIGURE 1.

CONSORT diagram.

Ethics approval was obtained from the University of Ottawa (H‐05‐20‐5584), The Ottawa Hospital (20230147‐01H), and the Princess Margaret Cancer Centre (21‐5060.3). The study was registered at Clinical Trials. Gov (NCT05441384). For additional information, please refer to the study protocol [20].

2.2. Participants

Canadian women caring for an adult cancer survivor (any cancer type, stages I‐III, completed treatments, no recurrence), fluent in English, experiencing clinical FCR (score of $\mathit{\ge }$ 13 on the Caregiver Version of the Fear of Cancer Recurrence Inventory‐Short Form [21, 22]), with a computer and internet access were recruited. We focused on women as research consistently demonstrates that they are at higher risk for caregiver burden [23] and FCR [2, 5]. Furthermore, FORT [13, 14, 15] has so far only been validated with women limiting the generalizability to men or nonbinary individuals. Recruitment occurred from September 2022 to December 2023. Flyers were shared widely across cancer and caregiving networks throughout Canada, with printed copies posted in key traffic areas of the Princess Margaret Cancer Centre and over 600 letters mailed to cancer survivors of The Ottawa Hospital inviting their FC to participate. Interested participants emailed the research coordinator and met with them or a research assistant via videoconference to assess their eligibility, obtain consent, and prepare them for group work. All participants provided informed consent before being randomized, completing the baseline measures and sociodemographic questionnaire.

2.3. Randomization and Procedures

We aimed to recruit 36 FC (four groups of nine participants; see sample size justification below). To minimize attrition associated with waiting to enrol participants, we used block randomization. Specifically, four sealed envelopes (two intervention and two WLCG) were created by the research coordinator and kept by a blinded independent research assistant. Once nine participants provided informed consent, they were randomized to a study group by the research assistant and completed their baseline assessment (T0). Post‐intervention assessment (T1) was conducted immediately after completion of FC‐FORT or 7 weeks post‐randomization (WLCG). Follow up assessment (T2) was conducted 3 months post‐intervention (FC‐FORT) or 3 months after T1 (WLCG). Participants in the intervention group were also asked to complete additional measures at sessions 1, 4 and 7, and a semi‐structured exit interview. WLCG participants were offered FC‐FORT after completing the T2 assessment.

2.4. Therapist Recruitment, Training and Supervision

Three therapists were recruited to facilitate FC‐FORT. Therapist competency was determined by the following criteria: (1) registered allied health professionals with expertise in counselling/psychotherapy and psychosocial oncology, (2) ability to offer virtual services across Canada, (3) at least 5 years of experience in psychosocial oncology, and (4) led at least one support group.

To enhance adherence to treatment, therapists were provided with a standardized FC‐FORT manual, a virtual training session (2h) with the research team, and weekly 30‐min supervision offered by one of the study psychologists (SL). The research coordinator and assistant reviewed the videos of all sessions using a fidelity checklist to assess treatment adherence. If adherence was less than 80% on any session, the study psychologist (SL) provided additional feedback and supervision to the therapists.

2.5. Study Intervention

Like the original FORT [13, 14, 15], FC‐FORT is a standardized and manualized therapist‐led intervention (see Table 1). FC‐FORT consists of 7 consecutive weekly group sessions of 120 min each, offered via videoconference, and between session assignments. It builds upon FORT's original blended theoretical model of FCR [24] with some adaptations made to represent caregivers' realities [16] (e.g., protective buffering). Main components include Kissane's Cognitive‐Existential therapy [25, 26], principles of group therapy, and Cognitive Behavioural Therapy‐based techniques. Key goals of FC‐FORT include: (1) distinguishing worrisome symptoms from benign ones; (2) identifying FCR triggers and inappropriate coping strategies; (3) facilitating the learning and use of new coping strategies, such as self‐care, relaxation techniques and cognitive restructuring; (4) increasing tolerance for uncertainty; (5) promoting emotional expression of specific fears that underlie FCR and reducing protective buffering; and (6) re‐examining life priorities and setting realistic goals for the future. For additional information on FC‐FORT, please refer to our adaptation [16] and protocol articles [20].

TABLE 1.

Overview of FC‐FORT sessions.

Session 1: Introduction to the group, learning new skills to deal with FCR (120 min)	Introduction by each participant with a focus on their experience with fear of cancer recurrence (FCR). Introduce ABC model of therapy, FCR model, cognitive restructuring and identify triggers. Teach cognitive restructuring and self‐care. Homework: Complete thought record and practice self‐care.
Session 2: Identifying knowledge gaps on FCR (120 min)	Discuss uncertainty and ways of regaining a sense of control. Discuss the patient's health care team. Teach progressive muscle relaxation. Homework: Complete thought log and practice daily progressive muscle relaxation.
Session 3: Increasing tolerance for uncertainty (120 min)	Discuss acceptable level of worry. Challenge faulty beliefs about benefits of worry. Discuss uncertainty and ways of regaining a sense of control. Teach the use of calming self‐talk & listening to relaxation files. Homework: Challenge faulty beliefs about benefits of worry. Practice calming self‐talk and progressive muscle relaxation daily.
Session 4: Building your coping skills (120 min)	Discuss maladaptive coping strategies. Address communication difficulties and teach new coping skills to address your fear of cancer recurrence. Teach guided imagery. Homework: Having a conversation about FCR. Practice guided imagery daily; challenge faulty beliefs about benefits of worry; complete thought record with behaviour.
Session 5: Getting deeper into underlying fears (120 min)	Provide psychoeducation about worry and the need for exposure to worse fears. Promote emotion expression and confront specific fears that underlie FCR by writing down worse fear scenario. Teach mindfulness exercise. Homework: Read worst case scenario daily. Practice self‐care & mindfulness exercise daily.
Session 6: Moving beyond specific fears (120 min)	Review exposure to worst case scenario exercise. Discuss ways of coping with some of the feared outcomes. Encourage participants to become re‐engaged with important life goals, people, or activities. Discuss what meaning the future and planning now have for them. Teach mindfulness exercise. Homework: Write down goals and priorities for the future, practice mindfulness exercise.
Session 7: Review and conclusion (120 min)	Review all content covered. Discuss future goals and setting new priorities. Promote the expression of saying good‐bye to the group and provide closure.

Groups consisted of a ‘closed’ format to enhance cohesiveness and consistency. Participants who missed more than two sessions were asked to stop the intervention and restart with the next available group to ensure they received FC‐FORT as intended. For analysis purposes, they were counted as dropouts. Before starting the intervention, participants received a standardized electronic and paper manual describing each session's activities and assignments.

2.6. Primary Outcomes: A Priori Benchmark for Success [20]

Feasibility in this pilot study was based on the (1) ability to recruit 36 FC in 15 months; (2) ability to randomise all 36 FC; (3) questionnaire completion of measures for 90% of participants; (4) ability to deliver FC‐FORT as intended as measured by a fidelity rating of above 80% on 75% of reviewed sessions.

Acceptability was based on the (1) ability to deliver FC‐FORT to 75% of FC within 15 months (maximum 25% dropout rate); (2) 80% completion of 5/7 sessions; (3) caregivers' satisfactory ratings $\mathit{\ge }$ 80% in terms of its content, therapists, and mode of delivery.

2.7. Secondary Outcomes

Clinical significance, or the potential practical importance of FC‐FORT on secondary outcomes, was determined using effect sizes with 95% confidence intervals. A systematic review of FC interventions [11] considered a small Cohen's d ($\mathit{\ge }$ 0.3) clinically meaningful at 3‐months post‐intervention. For the purposes of this pilot study, partial eta squared (η _p ²) will be reported and effect sizes of $\mathit{\ge }$ 0.01 will be considered clinically meaningful.

2.7.1. Measuring Secondary Outcomes

All measures were administered in English and online through Qualtrics.

FCR was measured using the Caregiver Version of the Fear of Cancer Recurrence Inventory—Short Form (FCRI‐SF). The FCRI‐SF has been validated with both cancer survivors and caregivers. A score of 13 or greater on this 9‐item instrument (range 0–36) indicates clinical level of FCR. The caregiver version of the FCRI has demonstrated good internal consistency (α = 0.95) and test‐retest reliability (α = 0.88).

Perceived risk of cancer recurrence was assessed using a one‐item question rated on a 5‐point Likert scale from ‘Much less likely’ to ‘Much more likely’: ‘Compared to persons of their age, how do you rate your family member's perceived risk of cancer recurrence?’.

Intolerance of uncertainty was measured with the Intolerance of Uncertainty Scale—Short Form (IUS‐12) [27] which measures reactions to uncertainty, ambiguous situations and the future. It has good internal consistency (α = 0.85) [27].

Uncertainty in illness was measured by the Mishel Uncertainty in Illness Scale Short‐Form (MUIS‐SF) [28]. It consists of 5 items rated on a 5‐point Likert scale. The MUIS‐SF has adequate internal consistency (α = 0.70) [28].

Positive beliefs about worrying were measured using the Why People Worry About Health Questionnaire [29]. It has excellent internal consistency (α = 0.90), and satisfactory temporal stability (r = 0.71) [29].

Coping was measured with the Cognitive Avoidance Questionnaire (CAQ) [30] that contains 25 items that measure avoidance coping. The CAQ has excellent internal consistency (α = 0.95), and good test‐retest reliability (r = 0.85) [30].

Protective buffering was measured with the Protective Buffering Scale [31]. This scale consists of 10 items rated on a 5‐point Likert scale. Internal reliability for this scale is good in both partners and cancer survivors (α = 0.80–0.89) [31].

Satisfaction with FC‐FORT was assessed using a one‐item question with a 5‐point Likert answer scale from ‘Very satisfied’ to ‘Very unsatisfied’: ‘How satisfied are you with the Family Caregiver—Fear of Recurrence Therapy?’.

Variables such as age, gender, ethnicity, marital status, family member role (e.g., spouse, partner, child, sibling), education level, medical histories for FC and survivors were collected using a sociodemographic questionnaire.

2.7.2. Additional Outcomes

Group cohesion was measured using the Group Cohesiveness Scale (CGS) [32] which consists of 7 items rated on a 5‐ point Likert scale. The GCS has good internal consistency (α = 0.87) [32].

Therapeutic alliance was measured using the Working Alliance Inventory—Revised Short Form (WAI‐SR) [33]. It is composed of 12 items rated on a 7‐point Likert scale. The WAI‐SR has corresponding versions for therapist and clients. The WAI‐SR has good internal consistency (α = 0.91–0.92) [33].

2.8. Exit Interviews

To gain further insights about the acceptability of FC‐FORT, participants in the intervention group were asked to take part in a one‐on‐one semi structured interview (30–60 min) via videoconferencing post‐intervention. Interviews were conducted by the research coordinator or assistant, and focused on participant expectations, general impact of FC‐FORT, helpful/unhelpful segments, group cohesion & therapeutic alliance, timing and length, homework practice, and usability of learnt material.

2.9. Sample Size Calculation

Sample size for the present pilot study was calculated based on the estimated sample size needed in a future RCT. For the RCT, a priori sensitivity power analyses were performed with G*Power 3.1 using a two‐sided (intervention vs. WLCG), type 1 error rate of 0.05% and 95% power, independent sample size of 57 participants per arm, and with a three‐time assessment (pre‐, post‐, and a 3‐month follow up). Under these conditions, an effect size of 0.40 (Cohen's d; based on average effect size of FCR interventions for patients) would detect a difference between FC‐FORT and a WLCG. Based on FORT's observed dropout rate and loss to follow‐up [13, 14, 15], an additional 20% participants per treatment group would be needed, thus requiring 68 participants per arm for a total of 136 study participants. This would mean conducting 16 groups of 9 FC (8 interventions and 8 WLCG). Assuming a 4‐year recruitment rate for the RCT, we needed to be able to recruit 4 groups (36 FC) in a period of 15 months during the present study to demonstrate feasibility of this future RCT.

2.10. Statistical Analyses

SPSS version 28 was used for the quantitative data and NVivo version 12 software for the qualitative data management and analyses. Descriptive statistics were used to report on the primary outcomes. Secondary outcomes were analysed using mixed ANOVA models, with Bonferroni corrections applied. Effect sizes and associated confidence intervals were calculated as an estimate of the effect size both over time (within group) and between groups. Interviews were recorded, transcribed verbatim, and double coded inductively by the research coordinator and assistant. Given the limited theoretical and conceptual information available regarding interventions addressing FCR in FC, conventional content analysis [34] was used.

3. Results

3.1. Sample Characteristics (Table 2)

TABLE 2.

Sample characteristics at baseline (T0, n = 15).

	Total	FC‐FORT (n = 7)	WLCG (n = 8)
Age, M (SD) [range]	50.2 (15.58) [27–74]	55.86 (13.93) [29–74]	45.25 (16.09) [27–72]
Race (%)
White	8 (53.3%)	5 (71.4%)	3 (37.5%)
South Asian	4 (26.7%)	2 (28.6%)	2 (25%)
Chinese	1 (13.3%)		2 (25%)
Black	1 (6.7%)		1 (12.5%)
Marital status (%)
Single, never married	3 (20%)		3 (37.5%)
Married/common‐law	11 (73.3%)	6 (85.7%	5 (62.5%)
Separated, divorced	1 (6.7%)	1 (14.3%)
Education (%)
Part of university/college	2 (13.3%)	2 (28.6%)
University/college	9 (60%)	4 (57.1%)	5 (62.5%)
Graduate school	4 (26.7%)	1 (14.3%)	3 (37.5%)
Occupational status (%)
Employed full‐time	7 (46.7%)	4 (57.1%)	3 (37.5%)
Employed part‐time by choice	3 (20%)		3 (37.5%)
Unemployed due to illness	2 (13.3%)	1 (14.3%)	1 (12.5%)
Retired	3 (20%)	2 (28.6%)	1 (12.5%)
Annual income (%)
$21,000–40,000	1 (6.7%)		1 (12.5%)
$41,000–60,000	3 (20%)	2 (28.6%)	1 (12.5%)
$61,000–80,000	1 (6.7%)	1 (14.3%)
$81,000–100,000	4 (26.7%)	2 (28.6%)	2 (25%)
Greater than $100,000	5 (33.3%)	1 (14.3%)	4 (50%)
Province (%)
Ontario	12 (80%)	5	7
Alberta	2 (13.3%)	1	1
Nova Scotia	1 (6.7%)	1
Recruitment method (%)
Hospital recruitment	3	2	1
Community partners and/or social media	12	5	7
Family Member's cancer type (%)
Breast	3 (20%)	2 (28.6%)	1 (12.5%)
Hodgkin's lymphoma	3 (20%)	1 (14.3%)	2 (25%)
Bladder	2 (13.3%)		2 (25%)
Ovarian	2 (13.3%)	1 (14.3%)	1 (12.5%)
Kidney	1 (6.67%)	1 (14.3%)
Leukaemia	1 (6.67%)		1 (12.5%)
Prostate	1 (6.67%)	1 (14.3%)
Oral	1 (6.67%)		1 (12.5%)
Glioblastoma multiforme	1 (6.67%)	1 (14.3%)
Family member's cancer stage (%)
I	1 (6.67%)		1 (12.5%)
II	3 (20%)	1 (14.3%)	2 (25%)
III	3 (20%)	2 (28.6%)	1 (12.5%)
IV	2 (13.3%)	2 (28.6%)
Unknown/other	6 (40%)	2 (28.6%)	4 (50%)
Time since diagnosis, M (SD) [range]	6.91 (7.09) [1–23]	5.2 (6.72) [1–17]	7 (6.86) [2–21]
Relationship with family member (%)
Spouse/partner	3 (20%)	2 (28.6%)	1 (12.5%)
Sibling	1 (6.7%)		1 (12.5%)
Parent	7 (46.7%)	2 (28.6%)	5 (62.5%)
Child	3 (20%)	3 (24.9%)
Other (e.g., aunt)	1 (6.7%)		1 (12.5%)
Receiving psychological services (%)
Yes	5 (33.3%)	3 (42.9%)	2 (25%)
No	10 (66.7%)	4 (57.1%)	6 (75%)
Perceived risk of cancer recurrence (%)
Equal to	4 (26.7%)	2 (28.6%)	2 (25%)
More likely	5 (33.3%)	1 (14.3%)	4 (50%)
Much more likely	6 (40%)	4 (57.1%)	2 (25%)

The mean age of participants was 50.2 years. Participants were White (53.3%), South Asian (26.7%), Chinese (13.3%) and Black (6.7%). Most were married (73.3%), college graduates (86.7%), employed full‐time (46.7%), and earned ≥$80,000 annually (60%). Participants were providing care to their adult children (40%), spouses/partners (20%), parents (27%), and other family members (13.3%). Participants had no relation to one another. The most prevalent types of cancer diagnoses were breast (20%) and lymphoma (20%), with a mean time since diagnosis of 6.1 years (SD = 7.1). Average (SD) score on the CV‐FCRI‐SF at baseline (T0) was 27.1 (7.2) for the intervention group and 26.1 (3.1) for the WLCG.

3.2. Primary Outcomes

3.2.1. Feasibility

Over 15‐months, 22 participants were interested and eligible, and 20 participants provided informed consent. Of these, 18 were randomized to the intervention group (n = 9) and the WLCG (n = 9), while 2 were not randomized due to the end of recruitment. Baseline assessment was completed by 15 participants (intervention = 7; WLCG = 8). The intervention group lost one participant post‐intervention (T1) and one at T2. No participants were lost in the WLCG. One WLCG participant did not complete their T1 assessment due to unforeseen circumstances but completed their T2 and T3; they were included in the final analyses. Overall questionnaire completion was 91.7% (SD = 6.6, Range = 86–100%). At the baseline (T0), post‐intervention (T1), and follow up assessments (T2), response rates were respectively 89%, 89%, and 100% for the WLCG and 100%, 86% and 86% for the intervention group. Therapists' adherence to treatment delivery was high with fidelity ratings of $\mathit{\ge }$ 80% (M = 86.7%, SD = 3.46, Range = 81–91) on 100% of sessions. Feasibility benchmarks were partially met. Namely, questionnaire completion and therapist fidelity benchmarks were achieved, whereas recruitment and randomization benchmarks were not.

3.2.2. Acceptability

FC‐FORT was delivered to 12 FC (33% dropout rate). Six FC dropped out post‐randomization, with more having dropped out from the WLCG [n = 4 (44.4%)] than the intervention group [n = 2 (22.2%)]. In total, 8 FC (66.7%) completed $\ge$ 5 sessions, with higher completion in the intervention group [n = 6 (85.7%)] than the WLCG [n = 2 (40%)]. Moreover, 4 FC dropped out after beginning group therapy, with more having dropped out from the WLCG [n = 3 (60%)] than the intervention group [n = 1 (14.3%)]. Reasons for dropout included being removed by the research team due to missing more than 2 sessions, scheduling issues, emotional readiness, and family member's cancer recurrence. FC satisfaction ratings with content, therapists, and mode of delivery was 80% (T1 = 86.6%; T2 = 73.4%). Acceptability benchmarks were partially met. Namely, FC satisfaction benchmark was achieved, whereas dropout and session completion benchmarks were not.

3.3. Secondary Outcomes

Effect sizes of ≥ 0.01 were found between group × time for FCR (F_(2,24) = 0.671, p = 0.520, η _p ² = 0.053, 95% CI [0, 0.231]) and perceived risk of recurrence (F_(2,24) = 0.204, p = 0.817, η _p ² = 0.017, 95% CI [0, 0.141]). They were also found across time for FCR, perceived risk of recurrence, intolerance of uncertainty, uncertainty in illness, positive beliefs about worrying and cognitive avoidance. See Table 3 for additional details. Moderately strong therapeutic alliance (Session 1: M = 39.80; Session 4: M = 44.83; Session 7: M = 43.17) and strong group cohesion (Session 1: M = 29.2; Session 4: M = 31.33; Session 7: M = 32.17) were observed throughout the intervention.

TABLE 3.

Mixed ANOVA analyses examining secondary outcomes.

Secondary outcomes	Baseline (T0)		Post‐Intervention (T1)		Follow‐up (T2)		Time × group	Main effect of time
	Intervention group (n = 7)	WLCG (n = 8)	Intervention group (n = 6)	WLCG (n = 8)	Intervention group (n = 6)	WLCG (n = 9)	F values, p values, and η p 2 [95% CI]	F values, p values, and η p 2 [95% CI]
	M (SD)	M (SD)	M (SD)	M (SD)	M (SD)	M (SD)
CV‐FCRI‐SF (range: 0–36)	27.14 (7.22)	26.13 (3.09)	21.5 (8.34)	26.5 (4.31)	24.17 (5.15)	25.67 (5.32)	F(2,24) = 0.671, 0.520, 0.053 [0, 0.231]	F(2,24) = 0.504, 0.611, 0.040 [0, 0.207]
Perceived risk (range: 1–5)	4.29 (0.951)	4 (0.756)	4.17 (1.169)	3.75 (0.886)	3.50 (1.76)	3.56 (1.01)	F(2,24) = 0.204, 0.817, 0.017 [0, 0.141]	F(2,24) = 0.821, 0.452, 0.064 [0, 0.250]
IUS‐12 (range: 12–60)	37.29 (10.01)	37.13 (8.59)	32.33 (12.53)	34.75 (10.07)	32.5 (11.57)	34 (9.10)	F(2,24) = 0.039, 0.962, 0.003 [0, 0.031]	F(2,24) = 0.523, 0.599, 0.042 [0, 0.210]
MUIS‐SF (range: 5–25)	14.14 (3.29)	14.25 (3.11)	13.33 (2.73)	14.13 (4.79)	14.33 (3.33)	13.78 (3.77)	F(2,24) = 0.101, 0.904, 0.008 [0, 0.095]	F(2,24) = 0.120, 0.888, 0.010 [0, 0.106]
WHQ (range: 13–65)	23.29 (6.58)	28.5 (12.49)	23.5 (8.85)	30.38 (11.17)	27.17 (13.50)	30.63 (13.70)	F(2,24) = 0.076, 0.927, 0.006 [0, 0.076]	F(2,24) = 0.286, 0.754, 0.023 [0, 0.164]
CAQ (range: 25–125)	64.29 (24.08)	64.75 (13.19)	54.17 (21.86)	62.38 (23.34)	56.33 (20.46)	64.88 (15.85)	F(2,24) = 0.037, 0.963, 0.003 [0, 0.027]	F(2,24) = 0.152, 0.860, 0.012 [0, 0.122]
PBS (range: 1–50)	35.43 (10.55)	40.5 (4.84)	29.83 (9.50)	38.88 (6.24)	32 (11.56)	39.88 (8.20)	F(2,24) = 0.039, 0.962, 0.003 [0, 0.041]	F(2,24) = 0.045, 0.956, 0.004 [0, 0.163]

Abbreviations: CAQ, cognitive avoidance questionnaire; CV‐FCRI‐SF, caregiver version—fear cancer recurrence inventory—short Form; IUS‐12, intolerance of uncertainty scale—short form; MUIS‐SF, Mishel uncertainty in illness scale short‐form; PBS, protective buffering scale; WHQ, why people worry about health questionnaire.

3.4. Qualitative Results (Table 4)

TABLE 4.

Qualitative results—themes and quotes from exit interviews (n = 6).

Overarching themes	Codes	Quotes
Expectations of FC‐FORT	Hoping to benefit from FC‐FORT	I was down and out, and it seems like nobody understands my situation. I mean, I have friends and family, but not in this situation. I thought it would be a good idea to be able to participate with people that are in the same boat as I am. (P22)
		I had high hopes that I would walk away with something. I didn't have a particular name or category or anything for it. But I was hoping that I would walk away with something that would make this easier. (P25)
		I wanted to be with a like‐minded group and, you know, to think about it differently. What are their coping strategies? How do they cope with it? (P26)
	Expectations about format	I first thought it was just like a study of what was needed kind of to help other caregivers in the future. Like, not so much me, other people that might need it. Because maybe this will help bring about more resources for caregivers or at least get the word out that there are resources, because there are, apparently, but you don't get told about them, right? (P28)
		My expectations were that I was going to be in a group with people like me, who are the parents of adult children, going through the caregiving experience of cancer. (P25)
		Well, [the research coordinator] had said that it was just going to be a small group, all women, caregivers. So that's what I expected. (P22)
Participants' experiences with FC‐FORT	Virtual format	I was happy about it [being an online group], because it gave me a degree of anonymity. It gave me a degree of control. It gave me a degree of safety and security for myself that I needed. (P25)
		I think that […] Zoom was the best format because of… there are two reasons for it. You don't have to commute, and […] we can see face to face. We can see the expressions of the people. (P26)
		In some ways I think we were able to be more open because we were still with the person, but not physically. So, you can, I think, be more open in a way, because you can just say “bye” and hit a button. […] You can see the person and talk to them, but it's still a little different than being in a room. […] I think with the group you can share more, maybe because you're not physically there, it's almost like talking to a bartender, right? You know what I mean? You talk to them, you leave, right? They never see you again. (P28)
		I'm going to say it may sound a bit out there, but it's almost like the universe sometimes puts a group together. You don't… although you don't know why, there's some little spider webs that weave things together. There's some common ground […]. So, in this one, yes, obviously there's the cancer, but also just the misfits of the different relationships that everybody was in the caretaking, but yet that common ground. So, I think being on Zoom or teams like that, it allows for that to just come to manifestation of its own accord. (P29)
	Content	[The exercises were] easy and easy to tap into. I don't have to find different space. I don't have to do anything. I could just… I could be anywhere, at any time. And so, those techniques I can just take a second and use the techniques. And so that's one thing that I don't I don't need to get a mat to lie down on. You know, I don't need a quiet space like this by myself. So that's what's really beneficial. (P25)
		I think exposure to multiple different modalities of like the mindfulness techniques and just realizing that when you experiment with different things, that maybe you wouldn't have naturally attempted or went to on your own, just that forced exposure, you find new ways that may be more successful than your old ways. (P29)
		No, just some sessions made me upset. But it's just, we were going deep, but it wasn't, it wasn't not helpful. (P22)
		Session five is really tough and [the facilitators] wanted to sit with me, but leaning into that stuff was really tough. (P30)
	Therapist facilitation	The way [the facilitators] have put the questions forward […] they were so much open‐ended questions. So, you cannot just say yes or no to it. You have to say that, okay, you know, this is how I feel. This is how I think I should be dealing with it. (P26)
		It felt like [the facilitators] cared about the group, and they listened. (P28)
		[The facilitators] were lovely. And they accepted. I felt that we were accepted and sort of hugged by them from the get‐go. (P30)
	Timing/Length	Time went by fast. By the time you looked at the clock, an hour had gone by. It was break time. And then it yeah, it really went by fast. So, it was really interesting. It kept me interested in the topics and everything. (P22)
		I know it's a long commitment to somebody to do longer than that. It couldn't have been any shorter. (P25)
		I think if you go too long, people will, you know, like anything, their train of thought and their interest waned, unfortunately, in our society already. So, I think seven is probably a good number. (P28)
	Homework	Like every week, I probably work a couple of days on the homework. Like a couple of days here, a day here and a day there. (P22)
		I mean, there was one [homework assignment] that was harder. So, [I did] all of them, except the worst‐case scenario one. […] that was very difficult. (P25)
		[…] so it's a time commitment. And I think I didn't realise that how important homework will be. (P26)
		Well, it depends… the written type of homework, I did pretty much every time. And then some of the other stuff depending on my week. (P28)
	Group cohesion	Just like everybody is in the same boat. Everybody. Everybody has the same story as mine. So, I mean, I felt connected to the group because we all have the same story. Being caregivers of people we love that have cancer. (P22)
		I mean, I think the more in depth we got, the greater [we connected] because there was a greater understanding, there was a greater trust and there is a greater exchange of information from all parties. So, from the first one, everybody, there's a bit of in trepidation and things like that. But then, you know, by week three, everybody kind of knows everybody. You kind of have the backs, like a bit of a of a thought in your mind about their story, right? They connect when they start to talk. You can relate to how it's impacting them or their loved ones and those kinds of things. (P29)
		A helpful thing was that engagement. […] So, I guess being present, you know, and then also, you know, participating, right? Not just sitting back and letting everybody else participate and just listen. (P26)
		You don't want to say it to somebody who's going to judge you for those feelings. So having that open exchange and dialogue and feeling that the circle was, you know, that closed group and there was a sense of trust that the information that was exchanged in there was going to be kept safe. And so that allowed for that freedom of exchange. And in addressing the elephant in the room. (P29)
		I did feel I thought we had a really strong sense of cohesiveness with the group. […] we were all very open and trusting and disclosing with each other of really raw things. And it was it was really great. People would use different language to describe their experience and, you know, I came to a point of just understanding my powerlessness. And then someone else described that as helplessness. And, you know, it was really great. (P30)
		[…] A great group of women, great and good facilitators. I love that, you know, that it was all women. (P29)
		I think, you know the opening circle… like opening, you know, check‐in and the check‐out is always helpful because it's that opening the group it's a pattern, right? And then the closure the saying goodbye. I think it's important, even on a weekly basis. (P29)
		Um, differences in experience [hindered my sense of connection]. Yeah, 100% like that. I mean, […] it's not my spouse, right? It's not my mom. […] It's my child. (P25)
		Not relating, feeling like an outlier, feeling outside of a shared experience. Their experiences were very shared. (P30)
		The fact that some people didn't show up was a problem. The fact that some people didn't have their camera on was a problem because we didn't know if they were there or not. (P30)
Perceived impact of FC‐FORT	Helpfulness in reducing FCR	I get to get up and get moving and I get to do stuff instead of sitting on the couch and thinking all day. I get to get up and start moving, walking, doing things for myself. Because if I don't take care of myself, I won't be able to take care of my [loved one]. (P22)
		It's empowered me to embrace the fear and ask the questions and make some decisions cognitively, like in my head in relationship to it. And so, I have that space now. I have that room now when I'm having those intrusive thoughts, when I'm, you know, when I am triggered, I have space now to step back and get into my head and look at it objectively before I fall off the deep end. […] I feel like I have more tools now to manage what happens. And I also feel like I will have forgiveness for myself with whatever I feel or do, with what happens. (P25)
		You know, […] I [can] take a backseat. I think I can concentrate more on myself and my health and say that, okay, this is the time that I have to take care of myself. I have taken care of others a lot. And now it's me. (P28)
		I feel like I'm in a better headspace. Even though there's things that are annoyed, I'm annoyed about, I feel like I have a better grounded sense about myself and I'm less reactive and less emotional than I would have been at the onset of the group so it has definitely had positive impacts and it's, you know, recognizable to other individuals that are close to me in my life that they can also see that. (P29)
	Importance of group	I would say the group made me see a lot of stuff, so I would say probably a nine. (P22)
		Very much depends. […] I hesitate to put someone into a situation that was at times as raw as it was in that group. Do I think the information presented was great? Yes. Do I think how it was presented was great? Yes. Do I think it was beneficial? Yes. Would I recommend it? Eesh. (P25)
		Yeah, absolutely [I would recommend]. Yeah. Like, I might tell them, you might go deep. You may discover things you didn't anticipate. But the skills are fabulous. (P30)
	Continued use of tools	My mind keeps coming back to [my loved one] and [their] diagnosis and it's a struggle to keep my mind focused on what I'm doing. […] So, the more I do [the exercises], it seems like the more that I can keep going, that I can do it without his situation popping up. So, I guess it's just practice and practice. (P22)
		I think, you know, just being more mindful of using those mindful techniques in my life and recognizing that the more you do it, the less of an effort is required. It becomes more like… It's like making memories. Creating that new habit. And then recognizing that it doesn't take much devotion to do it. Once you start doing it a few times, it's really easy. (P29)
		I can actually say it was extremely helpful because I now use these skills every day. You know, it might be a breathing thing, or it might be a thought log it might be, you're going down the rabbit hole. Just stop. Park it. You know, I am using the skills a lot. And like I said, they weren't new to me. But the penny dropped with them, and I could see the applications for them. (P30)
	Normalisation & reduction in loneliness of experience	[…] everybody was saying how they felt and what how the fear recurrence impacts them. And I could relate to that. (P22)
		Because it is it is helpful to talk to other people ‐ it doesn't sound like it would be, but it is—that are going through the same situation because my friends and family don't, I mean, they don't understand it, right? Like, I mean, they do, they try to, but they really don't. But until you're with someone that actually does, right, it actually is helpful to kind of understand that other people are in the same situation. And we can all kind of hopefully, not even help each other, but just kind of be there. (P28)
Suggestions for improvements	Content	Maybe the manual could, maybe, provide more explanation about some of the theory, maybe? (P30)
		I think, there could have been something, maybe, about things like the legal aspects when somebody is getting to that stage, whether it's now or not. I recognize that some people just don't really necessarily do their due diligence about like knowing about having wills done. There are legal matters, making sure that everybody has. they're both on all of […] their banking information […]. But it might have been a good opportunity to touch on it because sometimes if people are overloaded with stuff, it may be something that's overlooked, but the consequences of it could be grave. (P29)
	Similar group composition	But I think that that would be helpful even if the group is smaller, to have everybody in the same boat. I mean, I know everybody is in the same boat and I know I keep saying that, but it's just different when it's your child. It's just different. (P25)
		I think a similar cohort would have helped me a lot. There's pros and cons of diversity versus, you know, homogeneity. But for me, I really would have liked to been with spousal caregivers. Okay, so that's a big recommendation. (P30)
	Timing/Length	I also think that for some of the sessions that we did, there was too much for the 2h and at the same time allow for the type of sharing that was encouraged in the sessions. So, I think I think some of them had too many exercises in them, if that makes sense. So, by either extending it longer or condensing it would have been beneficial. (P25)
		I think I would have instead of these seven sessions like it would if it was a 1.5 h and it spread out to 8 or 9 sessions, it will be good enough. (P26)
	Intervention administration	I think I'd make it a requirement that the camera should be on. Yeah, but I don't know if that's ethical or not. I'm trying to give people a choice, but that was a hindrance for me. (P30)
		One of the things I would say about […] my previous group, we were allowed […] that continuity with those of us who wanted to continue. But I think the difference with that group and this group is that that conversation (about exchanging contact information) was had at the beginning, so that we already were having outside contact as group members throughout. (P29)

3.4.1. Expectations of FC‐FORT

Prior to beginning the group, participants expressed hoping to gain knowledge/coping strategies to manage their FCR. Furthermore, shared experiences with other women FC were a salient expectation and reason to join the group. A few participants expressed that they expected the group would be more advisory style, rather than an active intervention. All participants understood that the group would be comprised of women FC, but some were under the impression that it would be homogenous in experiences (i.e., only parents).

3.4.2. Participants' Experiences With FC‐FORT

Overall, participants reported appreciating FC‐FORT's content and delivery, especially the variety of exercises, sharing and relating to other FC, therapists' facilitation, and the additional resources provided (e.g., workbook, audio files). Participants regularly completed the between session assignments. Primary barriers included time and types of exercises (i.e., individual preferences, emotionally challenging). All participants enjoyed the virtual format of the group. Specifically, being able to log off immediately, the lack of commute, the opportunity to be in a ‘safe’ environment while discussing difficult topics, and a degree of separation from other participants, with most expressing that they would not have joined otherwise. Participants reported strong group cohesion (i.e., sense of connection, support, shared understanding), which was positively influenced by the all‐women nature of the group, shared experiences, and videoconferencing format (i.e., ability to see each other). Participants' level of engagement (i.e., open camera, regular presence and active participation) significantly impacted FC’ sense of connection to one‐another with more engagement leading to increased cohesion. However, for some FC, the diversity of caregiving experiences sometimes made it harder to relate. Participants felt that the session length (2h) and group duration (7 sessions) were appropriate, though some felt certain sessions were rushed or lacked time for everyone to share.

3.4.3. Perceived Impact of FC‐FORT

Participants found FC‐FORT helpful in reducing their FCR and improving their emotion regulation. All participants rated the importance of the group $\mathit{\ge }$ 8/10. Most participants expressed that they would recommend the group to others, with 1 FC saying that it would depend on the person. Many participants identified the group as being a safe/understanding space to connect with others facing similar challenges, addressing the lack of understanding from others in their personal lives. The ability to connect with women “in the same boat” was very impactful. All participants continued using the tools and materials provided in the group to manage their FCR and other aspects of their lives (e.g., sleep).

3.4.4. Suggestions for Improvements

Participants suggested adding examples, definitions, clarifying wording, incorporating theory to some exercises, and providing resources on legal issues related to caregiving. Some recommended extending or adding sessions for better content pacing, a few expressed a personal desire for long term support, and one suggested incorporating a booster session. Some participants suggested smaller groups or grouping participants by similar caregiving experiences (e.g., spouses, parents). Finally, some recommended that open cameras should be mandatory throughout sessions and allowing outside contact with group members at the onset of the intervention.

4. Discussion

This study aimed to evaluate the feasibility, acceptability, and clinical significance of the newly adapted FC‐FORT intervention using a pilot, mixed‐method, parallel, two‐group (intervention vs. WLCG) RCT.

Regarding primary outcomes, feasibility and acceptability criteria were partially satisfied. Reaching FC proved to be difficult, with most participants recruited through social media. Our efforts recruiting in hospitals yielded minimal results, likely due to COVID‐19 restrictions and/or indirect recruitment strategies (i.e., reaching FC through patients, posted flyers). Moving forward, alternative recruitment approaches could include direct hospital recruitment (e.g., identifying FC in clinics, calling FC directly) in more Canadian provinces and modifying our recruitment language (use of ‘caregiver’). For many, ‘caregiver’ does not accurately describe their role with their loved one and can hold negative connotations (e.g., dependency, burden) [35]. Interestingly, this study included a higher proportion of FC caring for adult children and, similarly to our usability study [36], a younger population than typical in cancer caregiving research. These findings suggest that FC‐FORT may be more acceptable to some caregiver groups than others. While not mentioned by our participants, recruitment challenges may also have been influenced by the group format, intervention duration, and/or virtual delivery.

Furthermore, FC‐FORT was delivered to fewer participants than intended (dropout rate 8% higher than the expected 25% seen in FORT). Research consistently demonstrates that caregivers are a hard population to recruit and retain [18, 37]. A potential reason for this is that cancer FC typically carry high levels of caregiving burden and tend to prioritise their loved one resulting in limited time available for themselves [17, 18]. Slow recruitment rates impacted participants' ability to participate at the time of randomization (i.e., scheduling conflict, loss of interest), with significant effects on the control group suggesting that a waitlist approach may be impractical for FC. Potential improvements include establishing smaller group sizes to expedite randomization, homogenous group composition based on FC roles (e.g., parent, spouse) or patient cancer type, and a review of our randomization procedures with our advisory board.

Alternatively, rates for the completion of questionnaire packages and therapist adherence were high, highlighting the feasibility of data collection and administration of FC‐FORT. FC satisfaction of FC‐FORT's content, therapists, and mode of delivery was also strong. Exit interviews further corroborated that FC found FC‐FORT helpful in addressing their FCR and normalizing their caregiving experiences, and valued its online format. These results reflect the significant efforts invested in the adaptation and usability testing of FC‐FORT. Furthermore, they support the growing evidence that online, professionally facilitated psychological interventions improve health related quality of life, coping, and mental health outcomes in FC [38]. Participant suggestions for improvements will be reviewed with our advisory board.

Regarding secondary outcomes, both therapeutic alliance and group cohesion were rated highly and maintained over time, consistent with the qualitative data obtained from the exit interviews and previous iterations of FORT [13, 14, 15, 16]. Although not statistically significant, effect sizes of ≥ 0.01 were found for FCR, perceived risk of recurrence, intolerance of uncertainty, uncertainty in illness, positive beliefs about worrying and cognitive avoidance further suggesting the potential clinical relevancy of FC‐FORT.

At this time, FC‐FORT does not meet the necessary feasibility and acceptability criteria indicated to move forward with a larger RCT. However, results demonstrate that participants found FC‐FORT to be very likeable and findings suggest its potential effectiveness. It is recommended that our study protocol be thoroughly reviewed (specifically recruitment and randomization strategies) by our advisory board and that a second pilot study be conducted to gather additional data.

4.1. Study Limitations

The small sample size, high attrition, and sociodemographic characteristics challenge the generalizability of this pilot study. Future studies should include diverse populations, various delivery formats, and cultural adaptations. Volunteer bias may also have influenced results as participants were likely to be motivated and interested in the topic. Lastly, statistical findings should be interpreted cautiously due to the pilot's limited statistical power.

4.2. Clinical Implications

While FCR remains a common unmet need for FC, few interventions have been developed to address their needs [4, 5]. Our team was one of the first to adapt a validated patient group FCR intervention [13, 14, 15] to FC and to an online format [16]. Our findings indicate that FC‐FORT is satisfactory and is deemed helpful by FC in managing FCR. This represents a key step in providing evidence‐based, tailored interventions to FC experiencing FCR. Furthermore, results suggest that FC role (i.e., parent, spouse) may impact FCR experiences and that groups with similar caregiving experiences may be preferrable. Study findings also highlight the promising nature of adapting existing patient‐focused interventions for FC support.

5. Conclusions

While FC‐FORT was deemed helpful by FC and received a high satisfaction rating, there were significant issues with the pilot's feasibility (e.g., recruitment, randomization) and acceptability (e.g., dropout, session completion). These need to be addressed before FC‐FORT is deemed ready for a larger RCT to evaluate its effectiveness.

Author Contributions

J.L., R.N., J.A., J.W., C.M., S.D.L., A.M.L., J.J., M.J.E., S.L. all contributed to the adaptation of the FC‐FORT intervention, conceptualized this study, and helped obtain funding. J.L. and S.L. were responsible for the trial registration, recruitment of participants, administration of FC‐FORT and data management. J.L. drafted the manuscript. All authors critically reviewed the manuscript and approved the final version.

Ethics Statement

Ethical approval was granted from the University of Ottawa Ethics Committee (Reference Number H‐05‐20‐5584), The Ottawa Hospital Research Institute’s Ottawa Health Science Network Research Ethics Board (Reference Number 20230147‐01H) and The University Health Network’s Research Ethics Board (Reference Number 21‐5060.3). All participants provided informed consent by acknowledging that they have read and understood the Consent Form before beginning the group intervention.

Consent

We obtained informed consent from all participants in the study. Participation was voluntary.

Conflicts of Interest

The authors declare no conflicts of interest.

Data Availability Statement

The study manuals (therapists and patients) are available from the corresponding author on reasonable request.