Initial validation of the German version of the Attentional Function Index in a sample of haematological cancer survivors.

OBJECTIVE: To date, no German instrument exists to assess subjective levels of cancer-related cognitive impairments (CRCI) in cancer survivors. We translated the validated Attentional Function Index (AFI) into German and explored its psychometric properties.

METHODS: The validation sample consisted of 1,111 haematological cancer survivors mainly recruited from two cancer registries. Factorial structure was explored using principal component analysis, internal consistency via Cronbach's α, construct validity through correlational analyses (Pearson's r) and associations of patient characteristics with the AFI score via regression analyses.

RESULTS: In line with the original version, we revealed three factors, that is "effective action" (seven items), "attentional lapses" (three items) and "interpersonal effectiveness" (three items). The overall reliability α was .91. Verifying construct validity, the AFI score correlated positively with cognitive functioning (r = .64, p ≤ .01) and global QoL (r = .44, p ≤ .01), but negatively with fatigue (r = -.60, p ≤ .01) and depressive symptomatology (r = -.6, p ≤ .01). Older age (β = .12, p < .001), higher comorbidity (β = -.07, p = .02) and being male patient (β = .07, p = .01) were significantly associated with the AFI scores, but effect sizes were small.

CONCLUSION: The German translation of the AFI shows good psychometric properties and thus may be reasonably applied to measure the subjective level of CRCI in German-speaking oncological populations.