Association between Air Pollution and the Development of Rheumatic Disease: A Systematic Review

Table 4

Newcastle-Ottawa scale for quality of study assessment: cohort studies.

Cohort studies	Representativeness of exposed cohort	Selection of nonexposed cohort	Exposure ascertainment	Measured outcome not present at study onset	Comparability of cohorts	Outcome ascertainment	Sufficient Follow-up to allow outcome to occur	Adequacy of follow-up	Total
Chang, Taiwan, 2016 (RA)							0
Hart, USA, 2013 (RA)

For cohort studies, quality is assessed for four domains of selection (representativeness of exposed cohort, selection of the non-exposed cohort, ascertainment of exposure, and demonstration that the outcome of interest was not present at start of study), two domains of comparability (study controls for the most important factor and any additional important factor), and three domains of outcome (method of assessment of outcome, follow-up period, and adequacy of follow-up of cohorts). Points are assigned based on specified levels of quality within each domain to a maximum of 9 points.
denotes the rating system used in the NOS scale.