TABLE 3

Risk of Bias of Individual Studies Using CASP Tools

Focused QuestionRecruitment of PopulationExposureOutcomeConfoundingFollow-upPrecisionFit With Other Evidence
Cohort studies
 Stellrecht et al7//+//NA+
 Dewan et al8+++++/++
 Ramers et al9+/+//NA/+
 Byington et al11++++NA+/+
 Yun et al12+//++NA++
 Seiden et al13+/+++NA++
Diagnostic studyFocused questionReference standardVerification biasReview biasDefined disease statusMethods of testPrecisionImportant outcomes
 Mulford et al14++++/+++
Economic evaluationFocused questionCompeting alternativesEffectiveness of interventionEffects of interventionMeasurement of costsDiscountingIncremental analysisSensitivity analysis
 Nigrovic et al10++/NA++
  • +, no concern for bias; —, concern for bias; /, cannot tell if bias present; NA, not applicable to the study.