In a randomized trial, outcomes were not affected by intensive follow-up over 1 year.

OBJECTIVE: This study tested the impact on response and psychological measures of different follow-up schedules for participants in a study screening for type 2 diabetes risk. STUDY DESIGN AND SETTING: Participants were randomly allocated either to limited follow-up (n=213), with a single questionnaire at 1 year, or to intensive follow-up (n=218), with questionnaires sent 1, 6, and 12 months after screening. RESULTS: There were no statistically significant differences between the groups at 1 year in either response rate (P=.08) or change from baseline to 1-year follow-up in scores on the short form of the Spielberger State Anxiety Inventory (SSAI-SF; P=.13), although there was a statistically significant but small difference between the groups in the change score of the 12-item Well-Being Questionnaire (WBQ-12; P=.003). The proportion of participants completing a WBQ-12 measure at 1 year was significantly greater in the intensive follow-up group (P=.03). CONCLUSION: This study shows no important adverse effect of repeated questionnaire use on response rates or psychological outcomes and suggests that some measures may be more fully completed with intensive follow-up.