title: Health-related lost productive time (LPT): recall interval and bias in LPT estimates.
abstract: We examined the effect of interview characteristics (ie, recall interval, interview version) on estimates of health-related lost productive work time (LPT). Three versions of a telephone interview were administered using 7-day and 4-week recall periods. In a population-based survey, 7674 workers randomly were assigned to one of six interviews at contact; 615 participants received a follow-up interview. We found strong evidence of under-reporting using a 4-week recall period and a not significant trend in over-reporting LPT using a 7-day recall period. Of the three interviews, version 3 could be administered most quickly, on average, and yielded the most discriminating estimates of LPT by health condition (ie, headache, allergic rhinitis, and cold/flu). Our data suggest that variation in relatively short recall periods influences estimates of health-related LPT. A 2-week recall period may be optimal for minimizing overall reporting error but requires additional research to verify.
authors.affiliation: The AdvancePCS Center for Work and Health, Hunt Valley, Maryland, USA. wfstewart@geisinger.edu
authors.forename: Walter F
authors.initials: WF
authors.lastname: Stewart
authors.forename: Judith A
authors.initials: JA
authors.lastname: Ricci
authors.forename: Carol
authors.initials: C
authors.lastname: Leotta
mesh_terms: D000293:Adolescent; D000328:Adult; D015142:Baltimore; D002641:Chicago; D004526:Efficiency; D005260:Female; D006801:Humans; D007407:Interviews as Topic; D008297:Male; D011939:Mental Recall; D008875:Middle Aged; D012650:Self Disclosure; D018582:Sick Leave / Q000706:statistics & numerical data*; D011795:Surveys and Questionnaires