UI Author Year Population Exposure (All) Dietary assessment * Biomarkers * Comparator Statistical Analysis Outcome Design
8201444 Johnson 1994 a) Eligibility criteria clear? (y/n) y a) Exposure assessor blinded to outcome info? (y/n) n a) Method reported? (y/n) y a) One of the prespecified methods *** was used? (y/n) NA a) Level of the exposure in comparative categories (eg quartiles) is given (ranges)? (y/n) applicable for categorical analyses only n a) Adjusted or matched for ANY confounders (other than age and sex)? ** (y/n) nd a) Clear definition of outcome, including time of ascertainment? (y/n) y a) Prospective collection of data? (y/n) y
b) Sampling of population random or consecutive? (y/n) nd b) Outcome assessor blinded to exposure measurement? (y/n) n b) Food composition database or suppl composition reported? (y/n) n Time from sample collection to sample analysis reported? (y/n) NA b) Loss to follow-up <20%? (y/n) y b) Analysis was planned when cohort was formed? (y/n) y
c) Internal calibration of method perform (if FFQ)? (y/n/NA) n b) Justification of final adjusted model selection? (y/n) nd c) Do the authors specify a primary outcome? (y/n) y c) Justification of sample size (includes sample size calculations)? (y/n) n
OVERALL Grade (A/B/C): C
Explanation for Overall Quality Grade (if not Grade A): incomplete presentation of analysis

Check “NA” and skip all questions if study did not use dietary assessment or biomarkers


We will judge in the end if the set of confounders is adequate


Prespecified methods: HPLC, RIA kits, LC-MS/MS; EIA/Chemiluminescence

From: Appendix C, Evidence Tables: F-K

Cover of Vitamin D and Calcium
Vitamin D and Calcium: A Systematic Review of Health Outcomes.
Evidence Reports/Technology Assessments, No. 183.
Chung M, Balk EM, Brendel M, et al.

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