Table 2

Quality assessment study methodology, score obtained by each study on the checklist*

Hugli, 2011, SwitzerlandRighini, 2005, SwitzerlandHogg, 2005, UKWolf, 2008, USAKline, 2008, USA, NZDachs, 2010, USAKline, 2004, USA†Kline, 2010, USAPenaloza, 2012, France
(1) Were the patients selected in an unbiased fashion (consecutive or random sampling)?111111111
(2) Do they represent a spectrum of pretest probability the PERC is used for?0011110/1‡11
(3) Were the predictor variables assessed without knowledge of the outcome?111111111
(4) Were the outcomes assessed without knowledge of the predictor variables?111111111
(5) Were the outcomes defined accurately (especially PE)?111111111
(6) Was follow-up adequate (<10% lost to follow-up)?111111111
(7) Was there an explicit interpretation of PERC by clinicians in practice without knowledge of the outcome?000000000
  • *Yes=1, No=0.

  • †The study had two cohorts.

  • ‡Scores represent the score for the low risk and very low risk cohort, respectively.

  • PE, pulmonary embolism; PERC, pulmonary embolism rule-out criteria.