University at Buffalo - The State University of New York
Skip to Content
Study protocol, sample characteristics, and loss to follow-up: the OPPERA prospective cohort study. - PubMed - NCBI
Format

Send to

Choose Destination
See comment in PubMed Commons below
J Pain. 2013 Dec;14(12 Suppl):T2-19. doi: 10.1016/j.jpain.2013.06.006.

Study protocol, sample characteristics, and loss to follow-up: the OPPERA prospective cohort study.

Author information

1
Regional Center for Neurosensory Disorders, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina; Department of Endodontics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina; Department of Biostatistics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina.

Abstract

When studying incidence of pain conditions such as temporomandibular disorder (TMD), repeated monitoring is needed in prospective cohort studies. However, monitoring methods usually have limitations and, over a period of years, some loss to follow-up is inevitable. The OPPERA prospective cohort study of first-onset TMD screened for symptoms using quarterly questionnaires and examined symptomatic participants to definitively ascertain TMD incidence. During the median 2.8-year observation period, 16% of the 3,263 enrollees completed no follow-up questionnaires, others provided incomplete follow-up, and examinations were not conducted for one third of symptomatic episodes. Although screening methods and examinations were found to have excellent reliability and validity, they were not perfect. Loss to follow-up varied according to some putative TMD risk factors, although multiple imputation to correct the problem suggested that bias was minimal. A second method of multiple imputation that evaluated bias associated with omitted and dubious examinations revealed a slight underestimate of incidence and some small biases in hazard ratios used to quantify effects of risk factors. Although "bottom line" statistical conclusions were not affected, multiply-imputed estimates should be considered when evaluating the large number of risk factors under investigation in the OPPERA study.

PERSPECTIVE:

These findings support the validity of the OPPERA prospective cohort study for the purpose of investigating the etiology of first-onset TMD, providing the foundation for other papers investigating risk factors hypothesized in the OPPERA project.

KEYWORDS:

Temporomandibular disorder; cohort studies; epidemiologic methods; population statistics; proportional hazards models

PMID:
24275220
PMCID:
PMC3855654
DOI:
10.1016/j.jpain.2013.06.006
[Indexed for MEDLINE]
Free PMC Article
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Elsevier Science Icon for PubMed Central
    Loading ...
    Support Center