Objective: Studies of vasomotor symptoms (VMS) typically measure VMS via daily diaries completed at the end of the day. VMS can also be measured via diaries completed throughout the day or via physiological monitors—modalities with lower recall demands. We examined the degree of correspondence between three VMS measurement modalities: retrospective end-of-day/morning diaries, prospective reporting, and physiological monitoring. We determined whether discrepancies between measurement modalities varied by participant characteristics.
Methods: Twenty-five African-American women and 27 white women from the Pittsburgh site of the Study of Women’s Health Across the Nation who were experiencing VMS, had intact uterus and ovaries, and were free of medications affecting VMS underwent 4 days of ambulatory VMS and Actiwatch monitoring. VMS were recalled in end-of-day and morning diaries, reported prospectively during the day, and measured physiologically via a hot flash monitor. Associations between anxiety, sleep, or race/ethnicity and VMS measurement modality difference scores were examined using generalized estimating equations.
Results: Women underestimated the number of daytime VMS at the end of the day as compared with VMS that were prospectively reported or physiologically measured throughout the day. This pattern was particularly pronounced among African-American women (b [SE] = −3.01 [0.93], P = 0.001) and women with higher anxiety (b [SE] = −3.13 [1.53], P = 0.04). For nighttime VMS, women overestimated the number of VMS in the morning upon waking as compared with prospective measures, particularly if they had poorer sleep (higher wakening after sleep onset: b [SE] = 0.03 [0.008], P = 0.001).
Conclusions: Different measurement modalities yield different VMS estimates. Negative affect, sleep, and race/ethnicity may affect the recall of VMS.
From the 1Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA; 2Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA; 3Department of Epidemiology, University of Pittsburgh Graduate School of Public Health, Pittsburgh, PA; and 4Department of Psychology, University of Pittsburgh, Pittsburgh, PA.
Received February 13, 2013; revised and accepted April 4, 2013.
The content of this manuscript is solely the responsibility of the authors and does not necessarily represent the official views of the National Institute on Aging, National Institute of Nursing Research, Office of Research on Women’s Health, or National Institutes of Health (NIH).
Funding/support: P.F. was supported by Cardiovascular Behavioral Medicine training grant NIH T32 HL 007560. The Study of Women’s Health Across the Nation received grant support from the NIH, Department of Health and Human Services, through the National Institute on Aging, National Institute of Nursing Research, and NIH Office of Research on Women’s Health (grants U01NR004061, U01AG012505, U01AG012535, U01AG012531, U01AG012539, U01AG012546, U01AG012553, U01AG012554, and U01AG012495). This work was additionally supported by the NIH through the National Institute on Aging (grant AG029216 to R.C.T.).
Financial disclosure/conflicts of interest: None reported.
Address correspondence to: Rebecca C. Thurston, PhD, Department of Psychiatry, University of Pittsburgh School of Medicine, 3811 O’Hara Street, Pittsburgh, PA. E-mail: firstname.lastname@example.org