Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2006-1-20
pubmed:abstractText
Adherence to prenatal multivitamin/mineral supplement use is often measured by self-reports or pill counts. Although both measures were shown to overestimate adherence, measurement error is rarely considered. In this study, we examined measurement error in adherence to prenatal supplement use among pregnant women and demonstrated a calibration method to adjust for error. In a validation subsample (n=51) from a larger clinical study of supplementation, adherence was assessed by self-reports, pill counts, and a Medication Event Monitoring System (MEMS) bottle cap that recorded the date and time of each opening of the pill bottle. Mean adherence in the validation sample as measured by the MEMS (the gold standard) was 68%; thus, adherence measured by self-report (77%) and pill count (84%) reflected overestimation. The Pearson correlation coefficients of self-reports and pill counts to MEMS were 0.35 and 0.62, respectively. When adherence was defined as taking >or=75% of the pills prescribed, sensitivity and specificity were greater for pill counts (93 and 52%, respectively) than for self-reports (88 and 44%). The regression coefficient for pill count adherence from a linear regression on MEMS adherence was applied to pill counts from a larger sample (n=244). The adjustment significantly lowered the estimate of adherence from 74 to 64% (P<0.001) in this larger sample. In conclusion, our data show that both self-reports and pill counts overestimate adherence and that linear regression in comparison to an external standard such as MEMS can be used to correct for measurement error in adherence.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0022-3166
pubmed:author
pubmed:issnType
Print
pubmed:volume
136
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
479-83
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2006
pubmed:articleTitle
Correction for errors in measuring adherence to prenatal multivitamin/mineral supplement use among low-income women.
pubmed:affiliation
Department of Family, Nutrition and Exercise Sciences, Queens College of City University of New York, Flushing, NY 11367, USA. sunitha_jasti@qc.edu
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.