Abstract
Objective: To evaluate the reliability and validity of a food-frequency questionnaire (FFQ) and database designed to quantify phytoestrogen consumption. Methods: This study included 195 members of the California Teachers Study (CTS) cohort who, over a 10-month period, completed four 24-h dietary recalls, a pre- and post-study FFQ, and provided two 24-h urine specimens. Participants (n=106) in a parallel study (and 18 women who dropped out of the long-term study) completed a single recall and FFQ, and provided one 24-h urine specimen. Urinary phytoestrogens were determined using liquid chromatography-mass spectrometry. Reliability and validity were evaluated using Shrout-Fleiss intraclass correlations and energy-adjusted deattenuated Pearson correlations, respectively. Results: Correlations reflecting the reproducibility of the FFQ phytoestrogen assessment ranged from 0.67 to 0.81. Validity correlations (FFQ compared to dietary recalls) ranged from 0.67 to 0.79 for the major phytoestrogenic compounds (i.e., daidzein, genistein, and secoisolariciresinol) and 0.43 to 0.54 for the less common compounds. Compared to urinary levels, validity correlations ranged from 0.41 to 0.55 for the isoflavones and 0.16 to 0.21 for total lignans. Conclusion: Our isoflavone assessment is reproducible, valid, and an excellent tool for evaluating the relationship with disease risk in non-Asian populations. Further research is needed before these tools can accurately be used to assess lignan consumption.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 85-93 |
| Number of pages | 9 |
| Journal | Cancer Causes and Control |
| Volume | 17 |
| Issue number | 1 |
| DOIs | |
| State | Published - Feb 2006 |
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Keywords
- Dietary assessment
- Phytoestrogens
- Reliability
- Urinary excretion
- Validity
ASJC Scopus subject areas
- Oncology
- Epidemiology
- Cancer Research
Cite this
Reliability and validity of an assessment of usual phytoestrogen consumption (United States). / Horn-Ross, Pamela L.; Barnes, Stephen; Lee, Valerie S.; Collins, Christine N.; Reynolds, Peggy; Lee, Marion M.; Stewart, Susan L; Canchola, Alison J.; Wilson, Landon; Jones, Kenneth.
In: Cancer Causes and Control, Vol. 17, No. 1, 02.2006, p. 85-93.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Reliability and validity of an assessment of usual phytoestrogen consumption (United States)
AU - Horn-Ross, Pamela L.
AU - Barnes, Stephen
AU - Lee, Valerie S.
AU - Collins, Christine N.
AU - Reynolds, Peggy
AU - Lee, Marion M.
AU - Stewart, Susan L
AU - Canchola, Alison J.
AU - Wilson, Landon
AU - Jones, Kenneth
PY - 2006/2
Y1 - 2006/2
N2 - Objective: To evaluate the reliability and validity of a food-frequency questionnaire (FFQ) and database designed to quantify phytoestrogen consumption. Methods: This study included 195 members of the California Teachers Study (CTS) cohort who, over a 10-month period, completed four 24-h dietary recalls, a pre- and post-study FFQ, and provided two 24-h urine specimens. Participants (n=106) in a parallel study (and 18 women who dropped out of the long-term study) completed a single recall and FFQ, and provided one 24-h urine specimen. Urinary phytoestrogens were determined using liquid chromatography-mass spectrometry. Reliability and validity were evaluated using Shrout-Fleiss intraclass correlations and energy-adjusted deattenuated Pearson correlations, respectively. Results: Correlations reflecting the reproducibility of the FFQ phytoestrogen assessment ranged from 0.67 to 0.81. Validity correlations (FFQ compared to dietary recalls) ranged from 0.67 to 0.79 for the major phytoestrogenic compounds (i.e., daidzein, genistein, and secoisolariciresinol) and 0.43 to 0.54 for the less common compounds. Compared to urinary levels, validity correlations ranged from 0.41 to 0.55 for the isoflavones and 0.16 to 0.21 for total lignans. Conclusion: Our isoflavone assessment is reproducible, valid, and an excellent tool for evaluating the relationship with disease risk in non-Asian populations. Further research is needed before these tools can accurately be used to assess lignan consumption.
AB - Objective: To evaluate the reliability and validity of a food-frequency questionnaire (FFQ) and database designed to quantify phytoestrogen consumption. Methods: This study included 195 members of the California Teachers Study (CTS) cohort who, over a 10-month period, completed four 24-h dietary recalls, a pre- and post-study FFQ, and provided two 24-h urine specimens. Participants (n=106) in a parallel study (and 18 women who dropped out of the long-term study) completed a single recall and FFQ, and provided one 24-h urine specimen. Urinary phytoestrogens were determined using liquid chromatography-mass spectrometry. Reliability and validity were evaluated using Shrout-Fleiss intraclass correlations and energy-adjusted deattenuated Pearson correlations, respectively. Results: Correlations reflecting the reproducibility of the FFQ phytoestrogen assessment ranged from 0.67 to 0.81. Validity correlations (FFQ compared to dietary recalls) ranged from 0.67 to 0.79 for the major phytoestrogenic compounds (i.e., daidzein, genistein, and secoisolariciresinol) and 0.43 to 0.54 for the less common compounds. Compared to urinary levels, validity correlations ranged from 0.41 to 0.55 for the isoflavones and 0.16 to 0.21 for total lignans. Conclusion: Our isoflavone assessment is reproducible, valid, and an excellent tool for evaluating the relationship with disease risk in non-Asian populations. Further research is needed before these tools can accurately be used to assess lignan consumption.
KW - Dietary assessment
KW - Phytoestrogens
KW - Reliability
KW - Urinary excretion
KW - Validity
UR - http://www.scopus.com/inward/record.url?scp=30544431589&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=30544431589&partnerID=8YFLogxK
U2 - 10.1007/s10552-005-0391-6
DO - 10.1007/s10552-005-0391-6
M3 - Article
C2 - 16411057
AN - SCOPUS:30544431589
VL - 17
SP - 85
EP - 93
JO - Cancer Causes and Control
JF - Cancer Causes and Control
SN - 0957-5243
IS - 1
ER -