질 평가

문헌의 질은 본 연구자와 보조연구자(KJE, ISW)가 관찰연구 질 평가 도구인 The Newcastle-Ottawa Scale (NOS)를 활용하여 독립적으로 평가하였으며, 의견 불일치가 있을 경우 논의를 통해 합의를 이루었다 (Wells et al., 2000). NOS는 코호트와 환자-대조군 연구 평가도구가 각각 구분되어 있고, 코호트 연구는 코호트 선택, 코호트 비교가능성, 결 과 평가에 대해 평가할 수 있으며, 환자-대조군연구는 환자-대조군 선 택, 환자-대조군 비교가능성, 노출에 대해 확인하는 과정을 평가할 수 있도록 설계되어 있다. 본 연구주제에 따라 각 항목의 기준을 구체화하 였으며 다음과 같다(Table 5, Table 6).

Table 5. Quality Assessment Scheme for Cohort Studies Selection

1) Representativeness of the exposed cohort

a) truly representative of the average overweight or obesity at 0-6 years in the community : take account of their ethnic & country ★

b) somewhat representative of the average overweight or obesity at 0-6 years in the community : take account of their country ★

c) selected group of overweight or obesity at 0-6 years eg inpatients d) no description of the derivation of the cohort

2) Selection of the non exposed cohort

a) drawn from the same community as the exposed cohort ★ b) drawn from a different source

c) no description of the derivation of the non exposed cohort 3) Ascertainment of exposure

a) secure record (eg clinical records) ★ b) anthropometry or structured interview ★ c) written self report

d) no description

4) Demonstration that outcome of interest was not present at start of study a) yes ★

b) no

Table 5. Quality Assessment Scheme for Cohort Studies (continued) Comparability

1) Comparability of cohorts 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) ★

Outcome

1) Assessment of outcome

a) independent blind assessment(measurement) : reference to IDF (2006) or WHO (1998) or EGIR (1999) or NCEP–ATPIII (2001) or AHA(2004) ★ : If the outcome variable is continuous variable, then it is possible to be omitted.

b) record linkage : reference to IDF (2006) or WHO (1998) or EGIR (1999) or NCEP–ATPIII (2001) or AHA (2004) ★

c) self report d) no description

2) Was follow-up long enough for outcomes to occur a) yes (until 18 years of age or older) ★

b) no

3) Adequacy of follow up of cohorts

a) complete follow up - all subjects accounted for ★

b) subjects lost to follow up unlikely to introduce bias (lost to follow up ≤ 5%) ★ c) subjects lost to follow up >5% and description provided of those lost d) no statement

Note. SES=Social Economic Status; BMI=Body Mass Index; WC=Waist Circumference; IDF=International Diabetes Federation; WHO=World Health Organization; EGIR=European Group for the Study of Insulin Resistance; NCEP-ATPIII=National Cholesterol Education

Program-Adult Treatment PanelIII; AHA=American Heart Association

Note. The modified parts according to this study are printed in italic type.

Table 6. Quality Assessment Scheme for Case-Control Studies 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

Table 6. Quality Assessment Scheme for Case-Control Studies (continued)

3) Non-Response rate

a) same rate for both groups ★ b) non respondents described c) rate different and no designation

Note. SES=Social Economic Status; BMI=Body Mass Index; WC=Waist Circumference; IDF=International Diabetes Federation; WHO=World Health Organization; EGIR=European Group for the Study of Insulin Resistance; NCEP-ATPIII=National Cholesterol Education

Program-Adult Treatment PanelIII; AHA=American Heart Association

Note. The modified parts according to this study are printed in italic type.