Table 1

Quality assessment list

Criteria for quality score
Study population
1Study groups are clearly definedPositive if truly or somewhat representative of the average population (females>males, athletes, patients from primary or secondary care). Studies received also one point if they only included women, because the PFPS is more common in women than in man. Described recruitment of included patients
2Number of cases ≥50Positive if the total number of cases was ≥50
3Comparable groupsPositive if the study controls are comparable for age and gender
4Inclusion and exclusion criteriaPositive if inclusion and exclusion criteria were described
Inclusion: a clear definition of PFPS
Exclusion: a clear definition of the exclusion criteria
Assessment of outcome
5Definition of determinantPositive if a clear definition of outcome measure (variable that might be associated with PFPS) was described
Analysing and data presentation
6Data presentationPositive if risk estimates were presented or when raw data (numbers and percentages for dichotomous variables and means and SDs for continuous variables) were given that allow the calculation of risk estimates (OR or relative risks) and mean differences
7Control for confoundingPositive if the method used to control for confounding was described
8BlindingPositive if the outcome assessor was blinded on health status (PFPS versus controls) subjects
  • PFPS, patellofemoral pain syndrome.