Table 1.

Newcastle-Ottawa Quality Assessment Scale.

Selection
(1) Is the case definition adequate?
(a) yes, with independent validation: reference to IDF (2006) or WHO (1998) or EGIR (1999) or NCEP–ATPIII (2001) or AHA (2004) ★:
If the variable is continuous variable, then it is possible to be omitted.
(b) yes, eg record linkage or based on self reports
(c) no description
(2) Representativeness of the cases
(a) consecutive or obviously representative series of cases: all cases in a defined catchment area, or an appropriate sample of those cases (e.g. random sample) ★
(b) potential for selection biases or not stated
(3) Selection of Controls
(a) community controls ★
(b) hospital controls
(c) no description
(4) Definition of Controls
(a) no history of metabolic syndrome ★
(b) no description of source
Comparability
(1) Comparability of case and controls on the basis of the design or analysis
(a) study controls for age and sex (select the most important factor) ★:
It is considered to be adjusted if the scope of adult age is within five.
(b) study controls for any additional factor (SES or educational level or BMI or
weight or height or WC) ★
Exposure
(1)Ascertainment of exposure
(a) secure record (eg clinical records) ★
(b) structured interview where blind to case/control status ★
(c) interview not blinded to case/control status
(d) written self report
(e) no description
(2) Same method of ascertainment for cases and controls
(a) yes ★
(b) no
(3) Non-Response rate
(a) same rate for both groups ★
(b) non respondents described
(c) rate different and no designation