Postal research: too many problems?
Bates
S M
SM
Rogstad
K E
KE
D000293:Adolescent; D000328:Adult; D015982:Bias; D003219:Confidentiality; D003430:Cross-Sectional Studies; D006801:Humans; D010349:Patient Compliance; D011177:Postal Service; D015203:Reproducibility of Results; D012107:Research Design; D012201:Reward; D012680:Sensitivity and Specificity; D013048:Specimen Handling / Q000379:methods*