Nursing Competency Scale for Patients With Comorbid Cancer and Dementia in Acute Care Hospitals (NCS‐CD): Development and Validation

ABSTRACT

Objectives

This study aimed to develop a Nursing Competency Scale for Patients with Comorbid Cancer and Dementia in Acute Care Hospitals (NCS‐CD) and examine its reliability and validity.

Methods

The study was conducted in two phases. In Phase 1, a preliminary scale was developed based on interviews with Japanese specialists in cancer and dementia nursing and a comprehensive literature review. The draft was refined through a questionnaire survey of 10 specialists and a consensus meeting with five experts. In Phase 2, the reliability and validity of the scale were evaluated using data from 305 nurses working in acute care hospitals. Exploratory and confirmatory factor analyses were conducted to assess construct validity. Criterion‐related validity was examined using the Self‐Assessment Scale of Nursing Practice for Elderly People with Cognitive Impairment (SSNP). Internal consistency and test–retest reliability were assessed.

Results

The NCS‐CD comprised 23 items across five factors. Confirmatory factor analysis demonstrated acceptable model fit (χ²/df = 1.953, goodness‐of‐fit index [GFI] = 0.894, adjusted goodness‐of‐fit index [AGFI] = 0.867, comparative fit index [CFI] = 0.919, Tucker‐Lewis index [TLI] = 0.908, and root mean square error of approximation [RMSEA] = 0.056). The scale exhibited high internal consistency (Cronbach's alpha = 0.902) and good test–retest reliability (intraclass correlation coefficient = 0.746). Significant positive correlations were observed between the NCS‐CD and SSNP (r = 0.714, p < 0.001), supporting criterion‐related validity.

Conclusion

The NCS‐CD demonstrated preliminary reliability and validity for assessing nursing competencies in caring for patients with comorbid cancer and dementia in acute care hospitals. This scale can contribute to the improvement of nursing practice and educational programs for patients.

1. Introduction

The global population is rapidly aging (United Nations, Department of Economic and Social Affairs ²⁰²⁶), drawing increasing attention to the challenge of comorbidity in adults. In particular, the number of patients living with both cancer and dementia–conditions with high prevalence in later life–has been steadily increasing (Pilleron et al. 2019; World Health Organization ^2026a). A recent scoping review reported that the prevalence of cognitive impairment among cancer patients aged 60 and older was 6% in retrospective database studies and 26% in studies employing cognitive screening tools (Toledano et al. 2025).

Patients with comorbid dementia and cancer (patients with CCD) often follow treatment pathways that differ from those of patients with cancer alone. Evidence indicates that patients with CCD are less likely to receive chemotherapy, radiotherapy, or surgery (Caba et al. 2021). Additionally, they experience higher mortality rates and are more likely to prioritize quality of life (QoL) over aggressive cancer treatment when making decisions about their care (Caba et al. 2021).

Dementia not only complicates cancer treatment decision‐making (Griffiths et al. 2021; Ashley et al. ²⁰²¹), but also substantially disrupts the cancer care process by contributing to reduced treatment adherence and difficulties in managing treatment‐related side effects (Hopkinson et al. 2020; Griffiths et al. ²⁰²¹). Consequently, in acute care hospitals, nursing support that accounts for the complex and interacting effects of coexisting cancer and dementia is essential.

Optimizing care for patients with CCD requires more than simply combining standard cancer and dementia care practices; it necessitates the development of integrated nursing competencies that address both conditions simultaneously. In acute care settings, nurses must support ethical decision‐making by considering treatment appropriateness and balancing cancer care with dementia‐related needs (Ashley et al. 2021). They are also required to manage complex pain and symptom burdens (Witham et al. 2017; Hopkinson et al. ²⁰²⁰), apply specialized communication strategies tailored to patients' cognitive abilities (Ashley et al. 2021; Halpin et al. ²⁰²⁴), and facilitate multidisciplinary collaboration with cancer and dementia specialists (Farrington et al. 2022).

Nursing competency is defined as the ability to perform assigned tasks and actions using appropriate knowledge and skills to achieve positive outcomes for patients, nurses, and healthcare organizations (Mrayyan et al. 2023). Although several competency scales for dementia nursing have been developed, no comprehensive instrument currently captures the complex interactions between cancer and dementia in acute care settings. The development of such a scale would enable nurses caring for patients with CCD to engage in structured self‐reflection and self‐assessment, thereby empowering them to improve practice and promoting greater standardization of care. Accordingly, the purpose of this study was to identify nursing competencies specific to the care of patients with CCD and to develop a reliable and valid scale for objectively and comprehensively assessing these competencies.

2. Methods

2.1. Study Design

The Nursing Competency Scale for Patients with Comorbid Cancer and Dementia in Acute Care Hospitals (NCS‐CD) was developed using a cross‐sectional design comprising two phases. The overall development process of the NCS‐CD is presented in Figure 1.

FIGURE 1.

Development process of the NCS‐CD.

2.2. Phase 1: Creation of Draft Scale

2.2.1. Conceptual Framework

The conceptual framework for the NCS‐CD was derived from a prior concept analysis of dementia nursing competencies in acute care hospitals (Yamaguchi et al. 2019). This foundation was considered appropriate because, given the high prevalence of cancer patients in Japanese acute care settings (Ministry of Health, Labour, and Welfare, Japan ²⁰²⁶), the core competencies required for dementia nursing were assumed to overlap substantially with those needed to care for patients with CCD, enabling comprehensive item extraction.

2.2.2. Item Pool Development

Initial items were extracted from interview studies of advanced practice nurses who have cared for patients with CCD (Tsukagoshi et al. 2021; Tsukagoshi et al. ²⁰²⁵) and were supplemented by a literature review using the keywords “cancer,” “dementia,” and “support”. The review used 12 studies targeting patients with CCD, their families, and healthcare professionals in hospital settings (Bartlett and Clarke 2012; Courtier et al. ²⁰¹⁶; Witham et al. ²⁰¹⁷; McWilliams et al. ²⁰¹⁸; Cook and McCarthy ²⁰¹⁸; Hopkinson et al. ²⁰²⁰; Surr et al. ²⁰²⁰; Griffiths et al. ²⁰²¹; Ashley et al. ²⁰²¹; Martin et al. ²⁰²¹; Farrington et al. ²⁰²²; Hynes et al. ²⁰²²).

To generate the initial item pool, we created a matrix to systematically categorize the data (Appendix A). The competence attributes from Yamaguchi's concept analysis of dementia nursing (Yamaguchi et al. 2019) were arranged on the vertical axis, while the nursing support extracted from two previous interview studies and 12 studies on the care of patients with CCD included in the literature review were arranged on the horizontal axis. We mapped each nursing support description into the matrix cells where the horizontal and vertical concepts intersected. Duplicate content was consolidated, and concise descriptions were drafted to capture the specific nursing practices represented by the descriptions compiled within each cell.

Subsequently, an expert panel conducted a rigorous review of the initial 89 items. The panel comprised five researchers specializing in cancer or dementia nursing, all of whom held a Master's degree or higher. Following the expert panel's feedback, revisions, and consolidation, the item pool was finalized at 80 items.

2.2.3. Face and Content Validity

To evaluate face and content validity, a self‐administered questionnaire was distributed to 10 specialists in cancer or dementia nursing, recruited using convenience sampling. The panel included three certified nurse specialists (CNS) in cancer nursing, two CNS in gerontological nursing, one certified nurse (CN) in palliative care, one CN in cancer chemotherapy and immunotherapy nursing, one CN in breast cancer nursing, one CN in radiation oncology nursing, and one CN in dementia care. Data were collected between April and June 2024.

Content validity was assessed using the Item Content Validity Index (I‐CVI), as well as evaluations of item clarity and practicality. For the I‐CVI, participants rated each item on a four‐point Likert scale ranging from “1 = not relevant” to “4 = relevant” to indicate the extent to which each item reflected nursing care for patients with CCD. The percentage of items rated as 3 or 4 was calculated. According to the criteria proposed by Polit et al. (2007), items with an I‐CVI of less than 0.80 were excluded, resulting in the removal of six items. Item clarity and practicality were rated using a three‐point Likert scale (clear/practical, neither clear nor practical, or unclear/impractical). Participants were also invited to provide qualitative suggestions for improvement.

A pretest was subsequently conducted with five nurses who had experience caring for patients with CCD in acute care hospitals, recruited through convenience sampling. Participants provided feedback on item readability and comprehensibility. Based on these results, further revisions were made, and the final draft scale comprised 52 items.

2.3. Phase 2: Reliability and Validity Testing

2.3.1. Participants

Participants were registered nurses with experience caring for patients with CCD and were recruited from designated cancer hospitals providing acute care in central Japan. For factor analysis, a sample size of five to 10 participants per item, with a minimum of 200 participants, is recommended to ensure stability (Mokkink et al. 2018). Additionally, a minimum of 50 participants is recommended for test–retest reliability assessment (Terwee et al. 2007). Accordingly, the required sample ranged from 260 to 520 participants.

2.3.2. Procedure

An online, self‐administered questionnaire survey was conducted between September 2024 and March 2025 to evaluate the reliability and validity of the draft scale. Informed consent was obtained electronically by requiring participants to select an agreement checkbox before accessing the questionnaire. Two‐dimensional quick response (QR) codes were distributed to participating acute care hospitals, and participants used their personal digital devices (e.g., smartphones) to access and complete the survey. Data collection continued until the target sample size was achieved.

2.3.3. Measures

The questionnaire survey comprised three sections: participant characteristics and two measurement scales. Participants reported their age, clinical department, years of nursing experience, educational background, experience in nurse leader or managerial roles, and possession of CNS or CN qualifications. The primary instrument was the 52‐item draft scale version of the NCS‐CD. Items were rated on a four‐point Likert scale ranging from “1 = not practiced at all” to “4 = practiced very much.”

Criterion‐related validity was examined using the 19‐item Self‐Assessment Scale of Nursing Practice for Elderly People with Cognitive Impairment (SSNP) (Suzuki et al. 2016). The SSNP was selected as an external criterion because it emphasizes person‐centered care, prioritizing interpersonal relationships and the perspectives of older adults with cognitive impairment. The scale comprises four subdimensions: (1) “Care emphasizing the individual's perspective,” (2) “Care tailored to cognitive abilities and individual characteristics,” (3) “Care incorporating a socio‐psychological approach to anticipate potential problems,” and (4) “Care respecting individual wishes and values.” Responses were rated on a six‐point Likert scale ranging from “1 = never” to “6 = always,” with higher scores indicating greater adherence to person‐centered nursing. The SSNP has demonstrated strong internal consistency (Cronbach's alpha = 0.918), and permission for its use was obtained from the scale developer.

2.3.4. Statistical Analysis

Statistical analyses were conducted using IBM SPSS Statistics version 30 and IBM AMOS version 30. The level of statistical significance was set at 5%. The proportion of missing data was examined. Participants with missing responses for 10% or more of the draft scale were excluded, as their data were considered unreliable. Remaining missing values were imputed using mean substitution.

2.3.5. Item Refinement

The items were refined by item analysis. Item analysis was performed using ceiling and floor effects by mean/standard deviation, inter‐item correlation analysis, Item‐Total correlation analysis (I‐T analysis), and upper‐lower group analysis using the critical ratio method (upper‐lower group analysis). Upper‐lower group analysis was used to compare the scores of the top 25% high‐scoring group and the bottom 25% low‐scoring group for each item using a t‐test.

The exclusion criteria for items were as follows: ceiling effect (mean ± standard deviation > 4), floor effect (mean – standard deviation < 1), inter‐item correlation (r > 0.6), I‐T analysis (r < 0.3), and no significant difference in upper‐lower group analysis.

2.3.6. Construct Validity

Exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) were performed to confirm the structural validity of the NCS‐CD. First, EFA was conducted to determine the factor structure of the scale. The Kaiser–Meyer–Olkin (KMO) measure of sampling adequacy (KMO > 0.5) and Bartlett's test of sphericity (p < 0.05) were conducted to confirm the adequacy of the EFA. The number of factors was comprehensively evaluated and determined based on the Kaiser–Gutmann criterion (Kaiser 1960), scree plots, and the interpretability of the factors (Boateng et al. 2018). EFA was conducted using the generalized least squares method with promax rotation. Items with factor loadings exceeding 0.40 and other factor loadings less than 0.30 were accepted (Boateng et al. 2018). Each factor was named based on its interpretation.

CFA was conducted using the maximum likelihood method to verify the scale structure determined by EFA. The model fit was evaluated using the following criteria: chi‐squared/degree of freedom (χ²/df) < 3, goodness‐of‐fit index (GFI) > 0.90, adjusted goodness‐of‐fit index (AGFI) > 0.85, comparative fit index (CFI) ≥ 0.95, Tucker‐Lewis index (TLI) ≥ 0.95, standardized root mean square residual (SRMR) ≤ 0.08, and root mean square error of approximation (RMSEA) < 0.06 (Hu and Bentler 1999; Schermelleh‐Engel et al. ²⁰⁰³). In addition, the average variance extracted (AVE) was calculated to assess convergent validity, using the criterion of AVE ≥ 0.50 (Fornell and Larcker 1981).

2.3.7. Criterion‐Related Validity

Criterion‐related validity of the NCS‐CD was compared with the SSNP score using Pearson's correlation coefficient.

2.3.8. Reliability

Internal consistency was confirmed using Cronbach's alpha, McDonald's omega, and composite reliability (CR) based on CFA, with values > 0.7 considered acceptable (Fornell and Larcker 1981; Dunn et al. ²⁰¹⁴; Taber ²⁰¹⁸).

Temporal stability was assessed using the intraclass correlation coefficient (ICC) based on test–retest data. The retest questionnaire was distributed 2 weeks after the initial survey. Responses were matched using a six‐digit identification code consisting of the participant's birth month and the last four digits of their mobile phone number. ICC values were evaluated using the following criteria: > 0.9 is excellent, > 0.75 is good, > 0.5 is moderately good, and < 0.5 is poor (Koo and Li 2016).

2.4. Ethical Considerations

This study was approved by the ethics committee of Gunma University (Approval Number: HS2023‐213, February 29, 2024). Participants received detailed information regarding the study's purpose, procedures, voluntary participation, right to withdraw, protection of personal information, anonymity, data storage and disposal, and dissemination of findings. Informed consent was obtained electronically prior to participation.

3. Results

3.1. Response Rate and Analytical Sample

Questionnaires were distributed to 1550 nurses working at nine acute care hospitals. A total of 356 nurses responded (response rate: 23.0%). Among these respondents, 310 reported experience providing nursing care to patients with CCD. Three responses with missing data for 10% or more of the draft scale items, and two responses from nurses working in visiting nursing departments were excluded. The proportion of missing data in the draft scale ranged from one to three items (1.9%–3.8%). Consequently, data from 305 nurses (85.7% of respondents) were included in the main analysis. The proportion of participants included in the analysis at each facility ranged from 4.3% to 25.9% (9 facilities). For test–retest reliability, responses from 63 nurses who completed both the initial and follow‐up surveys without missing data were analyzed.

3.2. Participant Characteristics

Participant characteristics are summarized in Table 1. The largest age group was nurses in their 40s (33.1%), followed by those in their 30s (32.1%). Most participants worked in inpatient wards (92.1%). The most common length of nursing experience was 11–20 years (33.1%). Overall, 83.9% of participants had experience in nurse leader roles, and 42% held managerial positions.

TABLE 1.

Participant characteristics (n = 305).

Characteristics	Number	%
Age
20s	53	17.4
30s	98	32.1
40s	101	33.1
50s	48	15.7
60s	4	1.3
Missing	1	0.3
Clinical department
Inpatient ward	281	92.1
Outpatient department	15	4.9
Others	6	2.0
Missing	3	1.0
Years of nursing experience
≤ 5	37	12.1
6–10	66	21.6
11–20	101	33.1
21–30	82	26.9
≥ 31	19	6.2
Educational background
Technical school	133	43.6
Junior college	40	13.1
University	127	41.6
Graduate school	5	1.6
Experience in nurse leader role
No	48	15.7
Yes	256	83.9
Missing	1	0.3
Managerial role a
No	176	57.7
Yes	128	42.0
Missing	1	0.3
Certified nurse specialist/Certified nurse
No	283	92.8
Yes	22	7.2

^a Head nurse, assistant head nurse, or chief nurse.

3.3. Item Analysis

Among the 52 items in the draft scale, 11 items exhibiting ceiling effects were excluded. No items demonstrated floor effects. Eight item pairs exhibited strong inter‐item correlations (r > 0.6); therefore, seven items were excluded to enhance feasibility in acute care settings. No items exhibited low I‐T correlations (r < 0.3). In upper‐lower group analysis, all remaining items demonstrated significant differences between high‐ and low‐scoring groups (p < 0.001).

3.4. Construct Validity

3.4.1. Exploratory Factor Analysis

The results of EFA are presented in Table 2. EFA was conducted on the 34 items retained after item analysis. Sampling adequacy for EFA was confirmed (KMO = 0.903), and Bartlett's test of sphericity was significant (χ² = 2775, df = 253, p < 0.001). Based on the Kaiser–Guttman criterion, scree plot inspection, and factor interpretability, a five‐factor solution was selected. Eleven items with factor loadings below 0.40 were excluded. The final NCS‐CD comprised 23 items, with factor loadings ranging from 0.44 to 0.91. The five factors explained 59.9% of the total variance before rotation.

TABLE 2.

Factor Loadings and mean score of NCS‐CD.

Item		Factor 1	Factor 2	Factor 3	Factor 4	Factor 5	Mean	SD
Factor 1. Maximizing the patient's intrinsic capacity							3.21	0.13
1.	I examine how patients can help themselves to deal with adverse events during cancer treatment	0.720	−0.055	−0.031	0.086	−0.066	3.06	0.70
2.	I examine the impact of cancer treatment on dementia and quality of life	0.706	0.030	−0.036	−0.004	0.040	3.14	0.70
3.	I assess cancer distress symptoms that do not surface due to cognitive impairment from the patient's facial expressions, attitudes, and speech.	0.696	0.026	−0.047	−0.127	0.127	3.21	0.64
4.	I assess a patient's abilities without grouping them in with those who have dementia.	0.639	0.131	−0.014	−0.124	0.126	3.16	0.69
5.	I explain the treatment, tests, and care to ensure the patient is not confused.	0.442	0.233	0.120	0.006	−0.122	3.43	0.58
6.	I gather information about family members or supporters who can help with adverse events and safety measures during a patient's cancer treatment.	0.436	0.125	0.271	0.050	−0.158	3.26	0.69
Factor 2. Decision‐making support in cancer treatment							3.10	0.10
7.	I examine the appropriateness of the cancer diagnosis and treatment for the patient's life and livelihood.	0.046	0.790	−0.099	0.007	0.036	3.13	0.69
8.	I discuss with the patient, family, and health care providers any doubts about continuing cancer treatment.	0.014	0.752	−0.054	0.048	−0.014	3.12	0.75
9.	I infer a patient's cancer treatment intentions with family and medical staff based on the patient's words and actions.	0.023	0.599	0.050	0.139	−0.009	3.18	0.62
10.	I support cancer treatment decision‐making, taking into account the impact of dementia on cancer treatment.	0.235	0.501	−0.001	0.077	−0.015	2.93	0.71
11.	I examine care not only for safety, but also for the patient's quality of life.	−0.026	0.426	0.254	0.004	0.188	3.16	0.66
Factor 3. Developing an environment for cancer treatment							2.41	0.24
12.	I coordinate a staff of care workers and volunteers to ensure that patients feel comfortable coming to the hospital.	−0.100	0.098	0.836	−0.185	0.064	2.11	0.97
13.	I coordinate patients to come to the hospital with their family members so that they feel comfortable.	0.060	−0.137	0.739	0.132	−0.040	2.63	1.01
14.	I allow more time for examinations and tests for patients with dementia than for those without dementia.	−0.027	−0.154	0.653	0.136	0.135	2.34	0.91
15.	I gather information from patients' families about whether they feel burdened by outpatient visits and hospital stays due to cancer.	0.132	0.083	0.606	−0.085	−0.143	2.56	0.80
Factor 4. Coordinating community living							3.19	0.18
16.	I consider the necessity of social welfare services available to patients diagnosed with cancer or dementia.	−0.071	0.031	−0.064	0.912	−0.003	3.29	0.70
17.	I coordinate the living environment of patients after discharge, taking into consideration the burden of care on their families.	−0.112	0.164	0.077	0.625	−0.076	3.16	0.72
18.	I share information about patients' lives and medical conditions with community support workers (e.g., care managers, home health nurses) who care for them.	−0.007	0.121	−0.128	0.577	0.072	2.95	0.82
19.	I share information about cognitive disorders that require special consideration in treatment, testing, and care among medical professionals.	0.134	−0.102	0.130	0.544	0.116	3.35	0.63
Factor 5. Leveraging cancer and dementia care resources							2.64	0.34
20.	I discuss care with nurses who have received training in dementia care.	0.017	0.031	−0.046	−0.078	0.892	2.49	1.01
21.	I inform patients and their families that they can consult with dementia specialists (e.g., geriatricians, certified nurses in dementia nursing) when choosing cancer treatment.	0.011	0.102	−0.068	0.155	0.555	2.47	1.04
22.	I discuss care with cancer specialists (e.g., oncologists, certified nurse specialists in cancer nursing).	0.204	−0.238	0.048	0.204	0.451	3.15	0.85
23.	I refer to various resources, such as books, pamphlets, and electronic media, when I am unsure how to care for cancer patients with dementia.	−0.159	0.126	0.294	−0.036	0.436	2.45	0.84

Note: Bolded values indicate the highest item loadings on their respective factor.

Abbreviation: SD, standard deviation.

The factor names were assigned based on the conceptual meaning of the items. Factor 1, “Maximizing the patient's intrinsic capacity (6 items),” reflected nursing practices that respected the abilities of patients with CCD, such as assessing pain they cannot quite put into words due to dementia and evaluating cooperation with cancer treatment. Factor 2, “Decision‐making support in cancer treatment (5 items),” represented nursing support for treatment decisions that respected patients' values and QoL. Factor 3, “Developing an environment for cancer treatment (4 items),” encompassed nursing practices aimed at creating a safe and reassuring treatment environment. Factor 4, “Coordinating community living (4 items),” referred to nursing support for adjusting living environments to facilitate life outside the hospital. Factor 5, “Leveraging cancer and dementia care resources (4 items),” involved the effective use of resources such as specialists, trained nurses, and educational materials.

3.4.2. Confirmatory Factor Analysis

CFA was conducted using the five‐factor model identified in the EFA (Figure 2). The model demonstrated acceptable fit indices: χ²/df = 1.953, GFI = 0.894, AGFI = 0.867, CFI = 0.919, TLI = 0.908, SRMR = 0.057 and RMSEA = 0.056 (90% confidence interval: 0.048–0.064). Standardized factor loadings for all items ranged from 0.558 to 0.798 and were statistically significant (p < 0.001). The AVE values for each factor ranged from 0.418 to 0.495 (Table 3).

FIGURE 2.

Model of the NCS‐CD.

TABLE 3.

Reliability and Validity of NCS‐CD.

Factor	Cronbach's alpha	McDonald's omega	Composite Reliability	Average Variance Extracted	Test–retest
					ICC	95% confidence interval
NCS‐CD total	0.902	0.898	—	—	0.746	0.613–0.838
Factor 1. Maximizing the patient's intrinsic capacity	0.826	0.825	0.764	0.448	0.779	0.600–0.861
Factor 2. Decision‐making support in cancer treatment	0.827	0.830	0.830	0.495	0.667	0.505–0.785
Factor 3. Developing an environment for cancer treatment	0.774	0.784	0.782	0.476	0.646	0.476–0.769
Factor 4. Coordinating community living	0.777	0.784	0.786	0.482	0.650	0.482–0.772
Factor 5. Leveraging cancer and dementia care resources	0.731	0.749	0.739	0.418	0.628	0.452–0.757

3.5. Criterion‐Related Validity

The results of the correlation between the NCS‐CD and the SSNP are presented in Table 4. The total NCS‐CD score was strongly and positively correlated with the SSNP total score (r = 0.714, p < 0.001). Correlations between individual NCS‐CD factors and SSNP factors ranged from 0.253 to 0.675 (p < 0.001).

TABLE 4.

Correlation between NCS‐CD and SSNP.

	SSNP total	Care emphasizing the individual's perspective	Care tailored to cognitive abilities and individual characteristics	Care incorporating a socio‐psychological approach to anticipate potential problems	Care respecting individual wishes and values
NCS‐CD total	0.714**	0.675**	0.661**	0.577**	0.538**
Factor 1. Maximizing the patient's intrinsic capacity	0.586**	0.570**	0.437**	0.527**	0.545**
Factor 2. Decision‐making support in cancer treatment	0.572**	0.566**	0.486**	0.470**	0.470**
Factor 3. Developing an environment for cancer treatment	0.426**	0.412**	0.491**	0.257**	0.253**
Factor 4. Coordinating community living	0.589**	0.521**	0.472**	0.579**	0.485**
Factor 5. Leveraging cancer and dementia care resources	0.522**	0.475**	0.596**	0.366**	0.284**

Note: Pearson's correlation coefficient, **p < 0.01.

3.6. Scale Reliability

Reliability indices and test–retest results are presented in Table 3. The NCS‐CD demonstrated high internal consistency, with a Cronbach's alpha of 0.902 for the total scale and values ranging from 0.731 to 0.827. McDonald's omega for the total scale was 0.898, with factor‐level values ranging from 0.749 to 0.830. The CR for each factor ranged from 0.739 to 0.830. Test–retest reliability was acceptable, with an ICC of 0.746 (95% confidence interval: 0.613–0.838). ICC values for individual factors ranged from 0.628 to 0.667.

3.7. NCS‐CD Scores

Mean scores for each NCS‐CD item are presented in Table 2. The highest mean scores were observed for Factor 1, “Maximizing the patient's intrinsic capacity” (3.21, SD = 0.13), and Factor 4, “Coordinating community living” (3.19, SD = 0.18). Conversely, the lowest mean scores were observed for Factor 3, “Developing an environment for cancer treatment” (2.41, SD = 0.24), and Factor 5, “Leveraging cancer and dementia care resources” (2.64, SD = 0.34). The overall mean NCS‐CD score was 2.94 (SD = 0.37).

4. Discussion

4.1. Evaluation of the Scale

4.1.1. Sample Size and Representation

The final analysis in this study included 305 participants, of whom 63 participated in the verification of test–retest reliability. The response rate was relatively low at 23.0%. However, this likely reflects the highly specialized target population: nurses with experience in caring for patients with CCD.

From the perspective of sample size adequacy, this study satisfied the minimum criteria recommended by the COSMIN guidelines (Mokkink et al. 2018) for factor analysis—namely, a minimum of 200 participants and 5 to 10 respondents per item. This ensured sufficient stability for conducting EFA and CFA. Furthermore, for the evaluation of test–retest reliability, 63 participants were secured, exceeding the minimum requirement of 50 participants recommended by Terwee et al. (2007). Therefore, the psychometric properties were verified using a statistically adequate sample size.

In addition, the participants were predominantly in their 30s and 40s, which generally aligns with the age distribution of practicing hospital nurses in Japan (Japanese Nursing Association ²⁰²⁶). This consistency suggests that our sample reflects the general background of Japanese nurses. Thus, it supports the generalizability of our findings.

4.1.2. Psychometric Properties of the Scale

This study developed and psychometrically validated a nursing competency scale for patients with CCD. The NCS‐CD demonstrated satisfactory reliability and validity and comprises five subdimensions that capture key aspects of nursing care for this population. At the item level, competencies related to both dementia nursing and cancer nursing were evenly represented, resulting in a scale structure that reflects the complex clinical characteristics of patients with CCD.

EFA identified 23 items across five factors, supporting the proposed construct of the scale. Although the GFI, CFI, and TLI obtained in CFA did not fully meet the recommended thresholds, their values were close to the criteria (Hu and Bentler 1999; Schermelleh‐Engel et al. ²⁰⁰³), and the overall model fit was acceptable. Regarding convergent validity, while the AVE did not reach the ideal threshold of 0.50, the CR for all factors exceeded 0.70, demonstrating strong internal consistency. According to Fornell and Larcker (1981), if the AVE is less than 0.5, but the CR is higher than 0.6, the convergent validity of the construct is still adequate. Collectively, these findings provide preliminary evidence supporting the construct validity of the NCS‐CD.

As hypothesized, criterion‐related validity was supported by a significant positive correlation between the NCS‐CD and the SSNP. However, weaker correlations were observed between the NCS‐CD factors “Developing an environment for cancer treatment” and “Leveraging cancer and dementia care resources” and several SSNP subdimensions, including “Care that anticipates socio‐psychological problems” and “Care that respects individual wishes and values.” These weaker associations may reflect conceptual differences between the two instruments. The SSNP is grounded in person‐centered care principles central to dementia nursing, whereas the NCS‐CD specifically targets nursing competencies required to address the combined and interacting challenges of cancer and dementia. These findings suggest that, while the NCS‐CD shares common elements with existing dementia‐focused measures, it also captures unique competency domains relevant to patients with CCD.

Multiple approaches can be used to evaluate scale validity. In this study, the content validity was assessed using the CVI, which was calculated by specialists in cancer and dementia nursing. A CVI of 0.80 or higher is considered appropriate (Polit et al. 2007), as the scale adopts items with an I‐CVI of 0.80 or higher. This study extracted questionnaire items based on the concept of dementia nursing competencies and interviews with specialists experienced in caring for patients with CCD; the NCS‐CD reflects nursing practices that are highly relevant to clinical settings.

The NCS‐CD also demonstrated strong reliability. Cronbach's alpha, McDonald's omega, and the CR all exceeded the recommended threshold of 0.70 (Fornell and Larcker 1981; Dunn et al. ²⁰¹⁴; Taber ²⁰¹⁸), indicating high internal consistency. Test–retest reliability, assessed using the ICC, exceeded 0.70 (Koo and Li 2016), indicating acceptable temporal stability. Collectively, these results support the reliability of the scale.

4.2. Characteristics of the NCS‐CD

“Maximizing the patient's intrinsic capacity” involves leveraging the positive capabilities and potential (inner strengths) (World Health Organization ^2026b) that remain within a patient's mind and body to manage adverse events during cancer treatment. An approach that focuses on intrinsic capacity represents a shift from “disease‐centered” care to “life‐ and ability‐centered” care. Because patients with CCD experience compromised physical and mental well‐being from cancer treatment while facing cognitive decline, nursing care that leverages their strengths is extremely important. In practice, this concept helps nurses promote patient self‐care and participation by utilizing nonverbal cues, clear verbal communication, and family support. Managing the complex interplay between cancer treatment and cognitive decline requires more than just general cancer or dementia nursing. Thus, this approach represents a unique competency in CCD care, which is why this factor exhibited the highest mean score. It effectively incorporates dementia nursing perspectives into the primary cancer nursing task of adverse event management.

“Decision‐making support in cancer treatment” focuses on the impact of cancer diagnosis and the treatment related to the QoL of patients with CCD. When assisting with cancer treatment decisions for patients with dementia, considering the “bigger picture” is valuable (Griffiths et al. 2021). This includes evaluating the impact of dementia on prognosis, determining the appropriateness of the treatment, understanding the cumulative effects of treatment options, and assessing the ability to identify and report adverse events (Griffiths et al. 2021). Nurses play a crucial role in bridging the gap between complex cancer treatment decisions and the unique challenges presented by dementia. In this regard, this factor reflects an approach that integrates cancer nursing support, such as evaluating treatment options and side effect risks, with key dementia nursing considerations, such as decision‐making capacity, patient values, and family involvement.

“Developing an environment for cancer treatment” is centered on adjusting personnel and schedules to ensure that patients can receive cancer treatment with a sense of peace and security. The typically unfamiliar buildings and frequent, lengthy waiting times in cancer treatment settings make the environment uncomfortable for patients (Surr et al. 2020; Ashley et al. ²⁰²¹). Limited flexibility in treatment planning and consultation schedules may exacerbate behavioral and psychological symptoms of dementia and increase the need for safety interventions (Farrington et al. 2022). The lower mean score for this factor likely reflects the clinical difficulty of implementing such adjustments. Although nurses recognize its importance, these improvements are heavily constrained by organizational structures, such as hospital systems and staffing limitations. Nevertheless, this factor is essential. Providing structural support in cancer care integrates safe treatment delivery with environmental adjustments that foster a sense of security for patients with dementia.

“Coordinating community living” involves connecting patients with social welfare services or community support providers to create a more comfortable environment posttreatment. Patients with CCD and their families require more information about community‐based care (McWilliams et al. ²⁰¹⁸). Given that a cancer diagnosis and treatment can serve as an opportunity to coordinate social resources, it is important for nurses to be proactively involved in coordinating the external support environment. This factor is not merely about supporting the transition back to the community. It integrates care coordination to ensure the continuity of cancer treatment with daily life support for dementia care. Specifically, nurses share medical and care information with community support workers to balance uninterrupted cancer care with reduced family caregiver burden.

“Leveraging cancer and dementia care resources” focuses on utilizing available resources such as experts in cancer and dementia, trained nurses, as well as educational materials. Education in dementia care and consultation with specialists have been shown to improve dementia care skills (Yang et al. 2021; Urashima et al. ²⁰²²). As cancer treatment complexity increases, specialized nursing support in areas like immunotherapy and radiation therapy is indispensable (Galassi et al. 2023). Reports also suggest that the involvement of geriatric medicine specialists in cancer treatment is beneficial for patients with CCD (Farrington et al. 2022). It is crucial for nurses to actively utilize both cancer and dementia care resources. The range of available social resources increases precisely because a patient has both cancer and dementia (Tsukagoshi et al. 2025). The hope is that clinical nurses will make positive use of these resources. This factor represents the integration of specialized resources across different domains. Through interdisciplinary and interorganizational collaboration, it addresses both the advanced medical needs of cancer care and the complex care requirements of dementia care.

4.3. Implications for Nursing Practice

The NCS‐CD is a practical tool for comprehensively evaluating nursing competencies related to the care of patients with CCD. The NCS‐CD enables nurses to self‐evaluate their nursing and utilize the findings to improve the quality of nursing. Additionally, the NCS‐CD can be utilized to evaluate the effectiveness of nursing training programs related to patients. The NCS‐CD has a 23‐item, 5‐factor structure and comprises a relatively small number of questions. It also has no reverse items. Therefore, it can be easily utilized in clinical practice.

4.4. Limitations

There are several limitations to this study. First, this study was conducted in nine acute care hospitals in central Japan, and no comparative analysis was performed to evaluate regional differences among the samples. Additionally, the nurses surveyed had a high percentage of leadership experience and management positions, so it is unclear whether the scale adequately reflects the nursing competencies of less experienced nurses. Considering these limitations, caution should be exercised when applying these findings to nurses in other countries, different regions, or facilities other than acute care hospitals.

Second, this study utilized the same participants for both EFA and CFA. The overlap in participants may have affected the robustness and generalizability of the results. Future studies should employ cross‐validation using independent samples for EFA and CFA to strengthen the validity and reliability of the identified factor structure.

Third, because the NCS‐CD relies on self‐report measures, the responses may have been influenced by social desirability bias. Additionally, validity evidence is limited because the SSNP is not a gold standard for competencies in caring for patients with CCD; thus, the structural validity should be regarded as preliminary. Future research should further examine the scale's convergent, discriminant, known‐groups validity, and measurement invariance across nurse experience levels and care settings.

5. Conclusions

The NCS‐CD comprises 23 items across five factors and demonstrated strong reliability, with a Cronbach's alpha of 0.902. Criterion‐related validity was also supported. These findings support the reliability and validity of the NCS‐CD as an instrument for comprehensively evaluating nursing competencies related to the care of patients with CCD. This scale bridges different specialties by integrating cancer and dementia nursing expertise. By examining these combined competencies, the NCS‐CD helps clinical nurses manage the dual challenges of cancer and dementia while enhancing comprehensive care quality.

Author Contributions

Noriko Tsukagoshi contributed to the conceptualization, methodology, investigation, formal analysis, data curation, visualization, funding acquisition, and project administration of this study and drafted the original manuscript. Mitsuko Ushikubo contributed to the conceptualization, methodology, investigation, formal analysis, data curation, visualization, and supervision and assisted in the original draft preparation. Both authors were involved in writing, reviewing, and editing the manuscript. All authors read and approved the final manuscript.

Funding

This work was supported by Japan Society for the Promotion of Science, 24K13773.

Ethics Statement

Gunma University Ethical Review Board for Medical Research Involving Human Subjects. The reference number: HS2023‐213 Date of approval: February 29, 2024.

Conflicts of Interest

The authors declare no conflicts of interest.

Appendix A. Matrix for Extracting Draft Items (Part of the Item)

Previous studies Defining attributes a	Tsukagoshi et al. (2021)	Tsukagoshi et al. (2025)	Farrington et al. (2022)	Hynes et al. (2022)	Martin et al. (2021)	Ashley et al. (2021)	Hopkinson et al. (2020)
1. Respecting patient individuality
When nurses attend to patients with dementia, they value patient personhood and see not only their symptoms but also the individual's behaviors. Respecting patient individuality includes considering the patient's life history and regarding the patient as people. Regarding the patient as a person means nurses search for the meaning behind patients' behaviors and recognize patients' individuality.	I assess how well patients can manage the side effects of cancer treatment.	I assess cancer pain in patients with dementia by closely observing behavioral and verbal cues when the patients are unable to communicate pain effectively. I evaluate the patient's cancer pain using an objective assessment scale.		I engage in conversations with the patient and their family, focus on the patient's values, lifestyle, and preferred ways of living.			When explaining treatments, tests, and care, I monitor whether the information provided is overwhelming or whether the patient is experiencing confusion.
2. Applying ethical considerations
Nurses understand patients' authentic needs by carefully listening to patients' wishes and respecting their decision‐making because patients with dementia have difficulty clearly describing their thoughts. Nurses treat patients with dignity and respect their personal perspectives, values, beliefs, and preferences because nurses play an important role as advocates in the care relationship.	I determine care approaches that consider not only safety, but also the patient's QoL.	I discuss cancer treatment options with patients, while subtly assessing their preferences. I assess whether the proposed cancer treatment plan aligns with the patient's values, treatment goals, and daily life.			The patient and their family are informed about having the access to consultations with specialists in geriatrics and gerontological nursing.	I inform the patient and their family that they can consult dementia care specialists to help them make decisions regarding cancer treatment options.
3. Providing person‐centered care
Person‐centered care can be applied to acute care settings and can help nurses understand dementia from several aspects such as how patients experience the world, the causes of their behaviors, and how nurses view dementia care.		I ensure that the treatment room was comfortable and welcoming for the cancer patients.				I ensure that the same nurse provides as much care as possible to maintain consistency for the patient. Before initiating cancer treatment, I arrange an opportunity for the patient to visit the treatment room to familiarize themselves with the environment.
4. Possessing responsibility
Nurses make reasonable decisions balancing patients' needs and professional working requirements in acute care settings. Nurses have the responsibility to provide patient care while also allowing patients with dementia to maintain their autonomy.						When I face challenges in patient care, I consult medical textbooks, clinical guidelines, and digital resources to expand my knowledge.
5. Coordinating external environments
Nurses develop a positive, home‐like, friendly atmosphere to facilitate interconnections with patients. Nurses play a role in setting a social environment that provides social resources to connect patient with their communities.	I share information about cancer treatment with community care providers to support patients' daily lives. I adjust (coordinated) the home care environment, taking into account the caregiving burden associated with both cancer and dementia.	I use the available social welfare services tailored to support patients' with cancer and dementia.
6. Possessing care coordination and facilitation skills
Nurses coordinate care factors including awareness, assessment, monitoring, care planning, and management. Nurses play the role of facilitators because caring for patients requires a comprehensive approach, including performing medication reviews, urinary incontinence control, nutrition management, geriatric and psychiatric care, and consultation liaising.		I consult dementia care experts to optimize the patient's care plan. I collaborate with cancer care specialists to determine appropriate patient care strategies.	I collaborate with geriatric and gerontological nursing specialists to develop patient care plans. I worked closely with nurses trained in dementia care to review and refine care plans.			When a patient's family cannot accompany them to outpatient visits, I arrange for volunteer staff members to provide support. I communicate information about patients' cognitive status and living circumstances with the healthcare team.

Previous studies Defining attributes a	Griffiths et al. (2021)	Surr et al. (2020)	McWilliams et al. (2018)	Cook and McCarthy (2018)	Witham et al. (2017)	Courtier et al. (2016)	Bartlett and Clarke (2012)
1. Respecting patient individuality
When nurses attend to patients with dementia, they value patient personhood and see not only their symptoms but also the individual's behaviors. Respecting patient individuality includes considering the patient's life history and regarding the patient as people. Regarding the patient as a person means nurses search for the meaning behind patients' behaviors and recognize patients' individuality.	I contribute to cancer treatment planning by assessing how a patient's dementia may influence their ability to undergo and tolerate therapy.		When selecting cancer treatment plans, I consider the potential impact of therapy on the patients' dementia status and daily functioning.	I support cancer treatment planning by considering the effects of dementia on ‘patient's daily life and QoL.	I consult patient's their family regarding the patient's dementia status and accommodations required during cancer treatment.
2. Applying ethical considerations
Nurses understand patients' authentic needs by carefully listening to patients' wishes and respecting their decision‐making because patients with dementia have difficulty clearly describing their thoughts. Nurses treat patients with dignity and respect their personal perspectives, values, beliefs, and preferences because nurses play an important role as advocates in the care relationship.	If concerns arise regarding continuation of a therapy, I ensure that the patient, their family, and the clinical team discuss whether treatment should proceed.			Instead of generalizing findings across dementia patients, I assess each patient's decision‐making capacity individually.
3. Providing person‐centered care
Person‐centered care can be applied to acute care settings and can help nurses understand dementia from several aspects such as how patients experience the world, the causes of their behaviors, and how nurses view dementia care.					I support that the patients can safely and consistently attend cancer consultations and treatments.
4. Possessing responsibility
Nurses make reasonable decisions balancing patients' needs and professional working requirements in acute care settings. Nurses have the responsibility to provide patient care while also allowing patients with dementia to maintain their autonomy.		I ensure that the patients can safely and consistently attend cancer consultations and treatments.
5. Coordinating external environments
Nurses develop a positive, home‐like, friendly atmosphere to facilitate interconnections with patients. Nurses play a role in setting a social environment that provides social resources to connect patient with their communities.			I share cancer treatment information with community support workers, who take care of these patients.			I assess whether the patient had a caregiver to help them manage the side effects of the cancer treatment.
6. Possessing care coordination and facilitation skills
Nurses coordinate care factors including awareness, assessment, monitoring, care planning, and management. Nurses play the role of facilitators because caring for patients requires a comprehensive approach, including performing medication reviews, urinary incontinence control, nutrition management, geriatric and psychiatric care, and consultation liaising.							I seek guidance from dementia care specialists on best patient care approaches.

^a A concept analysis of dementia nursing competencies in acute care hospitals (Yamaguchi et al. 2019).

Data Availability Statement

The data that support the findings of this study are available from the corresponding author upon reasonable request.