Lost but not forgotten: patients lost to follow-up in a trauma database.

OBJECTIVES: To determine the characteristics of patients lost to follow-up and to identify if they are significantly different from those who are followed up in the context of a prospective randomized controlled trial. DESIGN: A retrospective review of a prospectively acquired trauma database. SETTING: A level 1 university-affiliated trauma hospital. PATIENTS: Two hundred and thirty-six patients treated for displaced intra-articular calcaneal fractures between April 1991 and December 1996. Of these, 198 were catcgorized as "attenders" and the remaining 38 were deemed "nonattenders." Demographics, severity of injury, intervention and post-treatment status of the 2 groups were compared. Demographic information, including age, gender, occupation workload, Workers' Compensation Board involvement and other standard trauma information were compared and the differences analyzed. RESULTS: The nonattenders were younger than the attenders, and there was a significantly increased proportion of Aboriginal Canadians in the nonattenders group. Attenders were more likely to be "skilled or semi-skilled clerical, sales, service or trades crafts" workers, and nonattenders were more likely to be "unskilled clerical, sales, service or labour" workers. Attenders were more likely to have a preoperative Bohler's angle of < 0 degrees, compared with a preoperative Bohler's angle of 0 degrees to 15 degrees for nonattenders. CONCLUSIONS: This trauma population is at higher risk of being marginalized by society and may not have the same accessibility to a study nurse or a hospital contact person. Patients lost to follow-up are a demographically and clinically different patient population from those who remain involved in a long-term prospective trauma study.