Table 5.

Characteristics of studies regarding the association of cognitive function with stress

Authors, date	Purpose	Study design/sampling	Sample size (n)/sample characteristics	Procedures and instruments	Key findings
Reid-Arndt and Cox, 2012	To examine the association among coping, stress, and cognitive difficulties	Cross-sectional/convenience sampling	n=36 Female, underwent surgery of breast cancer but before other treatments	Assessed the stress, coping, and cognitive difficulties 1-2 weeks following surgery Cognitive function  Objective measures: AVLT, COWAT, animal naming, WAIS-III, DST Stress  Self-report: IES-R	The level of self-reported stress was inversely related to deficits in memory, verbal fluency and attention
Hermelink et al., 2015	To examine the association between pretreatment CI and cancer-related PTSD	Cross-sectional/convenience sampling	n=226 Breast cancer (n=166) Female, Stage 0-IIIC, aged 18-65 Healthy control (n=60)	Cognitive function  Objective measures: TAP, TMT, DSF, DSB, VLMT  Self-report: EORTC-QLQ-C30, FEDA PTSD PTSD diagnostics	PTSD significantly predicted go/no go errors
Li et al. 2015	To examine the effects of PTSD on perceived CRCI	Cross-sectional/convenience sampling	n=201 Female, after breast surgery, aged 20-60	Cognitive function  Self-report: FACT-cog PTSD  Self-report: PCL-S	CRCI was significantly associated with the severity of PTSD symptoms
Hermelink et al., 2017	To test hypothesis that breast cancer patients’ cognitive function is affected by PTSD	Longitudinal/convenience sampling	n=226 Breast cancer (n=166) Female, newly diagnosed breast cancer, Stage 0-IIIC Healthy control (n=60)	Assessed at three times: Before chemotherapy or surgery (T1), 1 week after the completion of chemotherapy (T2), 1 year after T1 (T3) Cognitive function  Objective measures: VLMT, TAP  Self-report: EORTC-QLQ-C30, FEDA PTSD PTSD diagnostics	CRCI was mediated by PTSD

AVLT: Auditory verbal learning test, COWAT: Controlled Oral Word Association Test, WAIS-III: Wechsler Adult Intelligence Scale, DST: Digit Span Task, IES-R: Impact of Event Scale-Revised, PTSD: Posttraumatic stress disorder, TAP: Test of Attentional Performance, TMT: Trail making test, DSF: Digital Span Forward, DSB: Digital span backward, VLMT: Verbal learning and memory test, FEDA: Questionnaire of Experienced Deficits of Attendtion, CRCI: Cancer-related cognitive impairment, CI: Cognitive impairment, FACT-cog: Functional Assessment of Cancer Therapy-Cognitive Function, PCL-S: PTSD Checklist-Specific Stressor Version, EORTC-QLQ-C30: European Organization for Research and Treatment of Cancer Quality-of-life Questionnaire C30