MRC Epidemiology Unit

 

Epidemiological assessment of diet: a comparison of a 7-day diary with a food frequency questionnaire using urinary markers of nitrogen, potassium and sodium.

Day N, McKeown N, Wong M, Welch A, Bingham S

International Journal of Epidemiology. May 2001

(DOI : 10.1093/ije/30.2.309)

---

Validation studies in epidemiology: the relative precision of different designs.

Wong M, Day NE

Journal of epidemiology and biostatistics. Mar 2001

---