Table 2.

Characteristics of studies regarding the association of cognitive function with anxiety

Authors, date	Purpose	Study design/ sampling	Sample size (n)/sample characteristics	Procedures and instruments	Key findings
Lehto et al., 1999	To determine the relationship between anxiety and attention	Cross-sectional/ convenience sampling	n=45 Female, newly diagnosed with early-stage cancer (I or II), before surgery for breast cancer	Assessed the anxiety and attention 11 days before surgery Anxiety  Self-report: Anxiety subscale of POMS Attention Cognitive function  Objective measures: DSF, DSB, SDMT, NCPC Self-report: AFI	Significant inverse relationship between anxiety and self-perceived attention No significant relationship between anxiety and attention as measured by objective measures
Cheung et al., 2012	To examine CI and its relationship with psychological factors in Asian breast cancer patients receiving chemotherapy	Cross-sectional/ convenience sampling	n=166 Undergoing chemotherapy (n=85) No chemotherapy (n=81)	Assessed anxiety and cognitive function in 25-min interview Cognitive function  Self-report: FACT-cog Anxiety  Self-report: BAI	A significant and inverse relationship between the level of anxiety and cognitive function in breast cancer patients undergoing chemotherapy
Wirkner et al., 2017	To investigate cognitive function and emotional states in breast cancer patients	Crosssectional/ convenience sampling	n=51 Breast cancer (n=20) Healthy control (n=31)	Cognitive function  Objective measures: TAP, WMS-R, VLMT  Self-report: Questionnaires Anxiety  Self-report: STAI	A significant and inverse relatioanship between anxiety and cognitive function (memory and concentration) in breast cancer patients

POMS: Profile of Mood States, DSF: Digital Span Forward, DSB: Digital Span Backward, SDMT: Symbol Digit Modalities, NCPC: Necker cube pattern control, AFI: Attention Functional Index, TAP: Test Battery for Assessment of Attention, WMS-R: Wechsler Memory Scale-Revised, VLMT: Verbaler lern- und Merkfahigkeitstest, STAI: State Trait Anxiety Inventory, BAI: Beck Anxiety Index, CI: Cognitive impairment, FACT-cog: Functional Assessment of Cancer Therapy-Cognitive Scale