Background/Aims

Data integrity in multicenter and longitudinal studies requires implementation of standardized reproducible methods throughout the data collection, analysis, and reporting process. This requirement is heightened when results are shared with participants that may influence health care decisions. A quality assurance plan provides a framework for ongoing monitoring and mitigation strategies when errors occur.

Methods

The Diabetes Control and Complications Trial (1983–1993) and its follow-up study, the Epidemiology of Diabetes Interventions and Complications (1994–present), have characterized risk factors and long-term complications in a type 1 diabetes cohort followed for over 40 years. An ancillary study to assess bone mineral density was implemented across 27 sites, using one of two dual x-ray absorptiometry scanner types. Centrally generated reports were distributed to participants by the sites. A query from a site about results that were incongruent with a single participant’s clinical history prompted reevaluation of this scan, revealing a systematic error in the reading of hip scans from one of the two scanner types. A mitigation plan was implemented to correct and communicate the errors to ensure participant safety, particularly among those originally identified as having low bone mineral density scores for whom antiresorptive treatment may have been initiated based on these results.

Results

The error in the analysis of hip scans from the identified scanner type resulted in lower bone mineral density scores in scans requiring manual deletion of the ischium bone. Hip scans with original T-score ≤ −2.5 (n = 84) acquired on either scanner were reviewed, and reanalyzed if the error was detected. Fourteen scans were susceptible to this error and reanalyzed: nine scans were reclassified from osteoporosis to low bone mineral density, one from low to normal bone mineral density, and four were unchanged. All errors occurred on one scanner type. An integrated communication and intervention plan was implemented. The nine participants whose scans were reclassified from osteoporosis to low bone mineral density were contacted; five were using antiresorptive treatment, all of whom had other risk factors for fracture beyond these scan results. Review of all hip scans with a T-score > −2.5 (n = 371) using this scanner type identified 27 additional hip scans that required reanalysis and potential reclassification: 1 scan was reclassified from osteoporosis to low bone mineral density, 11 from low to normal bone mineral density, and 15 were unchanged.

Conclusion

The impact of an analysis error on participant safety, specifically when the initiation of unnecessary treatment may result, necessitated implementation of a coordinated communication and mitigation plan across all clinical centers to ensure consistent messaging and accurate results are provided to participants and their local care providers. This framework may serve as a resource for other clinical studies.