Stephanie A Kovalchik1. 1. Division of Cancer Epidemiology and Genetics, National Cancer Institute, 6120 Executive Blvd., EPS 8047, Rockville, MD 20852, USA. kovalchiksa@mail.nih.gov
Abstract
OBJECTIVE: To characterize current efforts and outcomes of individual patient data (IPD) collection among meta-analysts of randomized controlled clinical trials. STUDY DESIGN AND SETTING: Corresponding authors of meta-analyses of randomized controlled trials in general medicine with a binary endpoint were sent an e-mail survey inquiring about their efforts to obtain IPD. Descriptive statistics of each meta-analysis were extracted to evaluate their association with data seeking. RESULTS: Only 22 (4.2%) of the sampled meta-analyses included IPD. Of the 360 authors surveyed, 256 (71%) reported not seeking IPD: 48% thought that the undertaking would be too difficult, 30% thought that it was not necessary for their main analysis, 25% did not have sufficient time or resources, and 22% never considered it. Seeking IPD was not significantly associated with any trial characteristic examined, including whether subgroup analyses were performed. Authors who sought IPD obtained a median of two data sets (interquartile range=0-5). Unsuccessful contact (43%), refusal without explanation (21%), and lost or inaccessible data (20%) were the most common reasons why trial data could not be obtained. CONCLUSION: The infrequency of attempts made by meta-analysts to obtain participant data is an important contributor to the rarity of IPD meta-analyses. Published by Elsevier Inc.
OBJECTIVE: To characterize current efforts and outcomes of individual patient data (IPD) collection among meta-analysts of randomized controlled clinical trials. STUDY DESIGN AND SETTING: Corresponding authors of meta-analyses of randomized controlled trials in general medicine with a binary endpoint were sent an e-mail survey inquiring about their efforts to obtain IPD. Descriptive statistics of each meta-analysis were extracted to evaluate their association with data seeking. RESULTS: Only 22 (4.2%) of the sampled meta-analyses included IPD. Of the 360 authors surveyed, 256 (71%) reported not seeking IPD: 48% thought that the undertaking would be too difficult, 30% thought that it was not necessary for their main analysis, 25% did not have sufficient time or resources, and 22% never considered it. Seeking IPD was not significantly associated with any trial characteristic examined, including whether subgroup analyses were performed. Authors who sought IPD obtained a median of two data sets (interquartile range=0-5). Unsuccessful contact (43%), refusal without explanation (21%), and lost or inaccessible data (20%) were the most common reasons why trial data could not be obtained. CONCLUSION: The infrequency of attempts made by meta-analysts to obtain participant data is an important contributor to the rarity of IPD meta-analyses. Published by Elsevier Inc.
Authors: Jesse A Berlin; Jill Santanna; Christopher H Schmid; Lynda A Szczech; Harold I Feldman Journal: Stat Med Date: 2002-02-15 Impact factor: 2.373