University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA.
Surg Obes Relat Dis. 2013 Jul-Aug;9(4):514-9. doi: 10.1016/j.soard.2013.02.012. Epub 2013 Mar 15.
Retaining participants in observational longitudinal studies after bariatric surgery is difficult yet critical because the retention rate affects interpretation and generalizability of results. Strategies for keeping participants involved in such studies are not commonly published. The objective of this study was to review LABS retention strategies and present the 24-month retention data.
The LABS Consortium monitors an observational cohort study of 2458 adults enrolled before bariatric surgery at 10 centers within the United States (LABS-2). To maximize data completeness, the investigators developed retention strategies, including flexible scheduling, a call protocol, reminder letters, abbreviated visit options, honoraria, travel reimbursement, providing research progress reports, laboratory results, newsletters, study website, and retention surveys. Strategies for locating participants included frequent updates of contact information, sending registered letters, and searching medical and public records.
At 12 and 24 months, 2426 and 2405 participants remained active, with vital status known for 98.7% and 97.3% and weight obtained for 95.2% and 92.2%, respectively. There were 148 missed visits (6.2%) at 24 months primarily because of inability to contact the participant. Only 15 (0.6%) active participants at 24 months missed all follow-up visits. Although 42 participants could not be located or contacted at 6 months, data were obtained for 23 (54.7%) of them at 12 months, and of the 52 participants who could not be located or contacted at 12 months, data were obtained for 18 (34.6%) at 24 months.
Longitudinal studies provide the ability to evaluate long-term effects of bariatric surgical procedures. The retention achieved in LABS is superior to that of many published reports but requires extensive effort and resources. This report identifies useful retention strategies. Further research is needed to identify the efficacy and cost-effectiveness of specific retention strategies.
减重手术后观察性纵向研究中很难留住参与者，但这是至关重要的，因为保留率会影响结果的解释和推广。保持此类研究中参与者参与的策略并不常见。本研究的目的是回顾 LABS 的保留策略并呈现 24 个月的保留数据。
LABS 联盟监测了一项在美国 10 个中心进行的、2458 名成年人在接受减重手术前入组的观察性队列研究（LABS-2）。为了最大限度地提高数据完整性，研究人员制定了保留策略，包括灵活的安排、电话协议、提醒信、缩短就诊选项、酬金、旅行报销、提供研究进展报告、实验室结果、通讯、研究网站和保留调查。寻找参与者的策略包括频繁更新联系信息、发送挂号信和搜索医疗和公共记录。
在 12 个月和 24 个月时，2426 名和 2405 名参与者仍保持活跃，98.7%和 97.3%的参与者的生命状态已知，95.2%和 92.2%的参与者获得了体重数据。在 24 个月时有 148 次错过就诊（6.2%），主要是因为无法联系到参与者。只有 15 名（0.6%）在 24 个月时仍保持活跃的参与者错过了所有的随访就诊。尽管在 6 个月时有 42 名参与者无法找到或联系到，但在 12 个月时获得了其中 23 名（54.7%）的数据，而在 12 个月时无法找到或联系到的 52 名参与者中，有 18 名（34.6%）在 24 个月时获得了数据。
纵向研究能够评估减重手术程序的长期效果。LABS 实现的保留率优于许多已发表的报告，但需要大量的努力和资源。本报告确定了有用的保留策略。需要进一步研究来确定特定保留策略的疗效和成本效益。
