Table 2 Assessment of quality for a cohort study (adapted from Newcastle–Ottawa Scale)

Selection

Representativeness of the intervention cohort:

 • truly representative of children in the contemporary western world

 somewhat representative of children in the contemporary western world

 • selected group of patients, for example, only certain socioeconomic groups/areas

 • no description of the derivation of the cohort

Selection of the non-intervention cohort (in this case ‘normal weight’ during childhood):

 • drawn from the same community as the intervention cohort (in this case ‘at risk of overweight’ or ‘overweight/obese’ during childhood)

 • drawn from a different source

 • no description of the derivation of the non-intervention cohort

Ascertainment of exposure:

 • measurement by trained health professional

 secure record

 • written self-report

 • other/no description

Demonstration that outcome of interest was not present at the start of study:

 • yes

 • no

Comparability

Comparability of cohorts on the basis of the design or analysis:

 • study controls for age, sex and adult BM/percentage body fat

 • study controls for socioeconomic status

Outcome

Assessment of outcome:

 • independent assessment by trained health-care professional

 record linkage

 • self-report

 • other/no description

Was follow-up long enough for outcomes to occur:

 • yes, if mean adult age >35

 • no, if mean adult age ⩽35

Adequacy of follow-up of cohorts:

 • complete follow-up: all subjects accounted for

 subjects lost to follow-up unlikely to introduce bias: number lost ≤20%, or description of those lost suggesting no different from those followed

 • follow-up rate <80% and no description of those lost

 • no statement