Field-wide meta-analyses of observational associations can map selective availability of risk factors and the impact of model specifications

Abstract

Objectives Instead of evaluating one risk factor at a time, we illustrate the utility of “field-wide meta-analyses” in considering all available data on all putative risk factors of a disease simultaneously. Study Design and Setting We identified studies on putative risk factors of pterygium (surfer’s eye) in PubMed, EMBASE, and Web of Science. We mapped which factors were considered, reported, and adjusted for in each study. For each putative risk factor, four meta-analyses were done using univariate only, multivariate only, preferentially univariate, or preferentially multivariate estimates. Results A total of 2052 records were screened to identify 60 eligible studies reporting on 65 putative risk factors. Only 4 of 60 studies reported both multivariate and univariate regression analyses. None of the 32 studies using multivariate analysis adjusted for the same set of risk factors. Effect sizes from different types of regression analyses led to significantly different summary effect sizes (P-value < 0.001). Observed heterogeneity was very high for both multivariate (median I2, 76.1%) and univariate (median I2, 85.8%) estimates. No single study investigated all 11 risk factors that were statistically significant in at least one of our meta-analyses. Conclusion Field-wide meta-analyses can map availability of risk factors and trends in modeling, adjustments and reporting, as well as the impact of differences in model specification.

A novel graft option after pterygium excision: platelet-rich fibrin for conjunctivoplasty

“…Traditionally, several treatment modalities such as leaving bare sclera, primary conjunctival closure, conjunctival with/without limbal auto-grafting, and AMT have been used for ocular surface reconstruction after pterygium excision. 4,5,8,9 However, the most common challenging problem is recurrence rate after pterygium surgery. 16 The risk factors of pterygium recurrence are as follows: pterygium type and size, age of patient, environmental conditions, recurrent pterygium, and surgical technique.…”

“…1,2 Pterygium is more common in sunny, hot, dry, windy, dusty climate conditions, smoky environments, and tropical regions. 3,4 Ultraviolet radiation is the major risk factor, which damages cell proliferation cycle and induces abnormal cell proliferation, squamous metaplasia, goblet cell hyperplasia, inflammation, fibrosis, angiogenesis, and extracellular matrix breakdown. 5 Although the pathogenesis of pterygium remains unclear, it is acceptable as a stem cell disorder, which allows extension of the wing-shaped fibrovascular proliferation onto the cornea, and as an epithelia-mesenchymal transition.…”

“…5,8,9 Recurrence rates, the major concern after pterygium surgery, within these methods vary widely, therefore, adjunct metabolites like 5-fluorouracil (5-FU), mitomycin-C (MMC), or thiotepa have been used to improve the results. 4,8,9 However, there exists no surgical technique accepted as the gold standard treatment that prevents recurrence.…”

The Mass Production of Redundant, Misleading, and Conflicted Systematic Reviews and Meta‐analyses

“…Studies may be similar, but they are made deliberately different in one or more aspects. For example, in an empirical evaluation of 60 published studies on risk factors for pterygium (a very common eye condition), no pair of studies considered the exact same factors or used identical adjustments for “known” risk factors …”

Bayesian multivariate meta‐analysis of multiple factors

“…Pterygium is one of the most common eye conditions, and it may be related to many risk factors . Instead of reporting only 1 risk factor at a time, Serghiou et al collected the odds ratios of all putative risk factors for pterygium. Specifically, they identified 60 eligible studies reporting on a total of 65 risk factors.…”