Actigraphy scoring reliability in the study of osteoporotic fractures

San Francisco Coordinating Center and California Pacific Medical Center Research Institute, San Francisco, CA 94107, USA.
Sleep (Impact Factor: 4.59). 12/2005; 28(12):1599-605.
Source: PubMed


The editing and scoring of actigraphy data are important for calculating variables that describe sleep. Scoring is dependent on marking time points for when a participant got in and out of bed, plus time when the actigraph was removed. This placement of time points is subject to error. We examined interscorer reliability to determine if files scored by 2 different people were comparable.
Observational study.
A subset of 36 women taken from the latest biannual visit of the Study of Osteoporotic Fractures. All women had actigraphy data scored by 1 scorer for the Study of Osteoporotic Fractures staff, plus a blinded rescoring by an expert scorer at a different site.
The outcomes of interest from actigraphy are duration of in-bed interval, total sleep time, sleep latency, sleep efficiency, wake after sleep onset, total nap time, and total daytime minutes of watch removal. Clearly documented actigraphy scoring procedures were used. There were no significant differences between the expert scorer and the study scorer in sleep outcomes (all P values >.16 from a paired t test). There was a small but statistically significant difference between scorers for watch removal times (mean absolute difference 3.4 minutes +/- 5.4, P=.02). The intraclass correlation coefficients showed a high level of agreement (range, 0.84-0.99).
Even in a large study with 2 scorers, it is possible to use actigraphy as a measure of sleep without introducing interscorer measurement error. Using well-documented scoring and data-gathering procedures are essential for data quality control.

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    • "), and shows good inter-rater reliability (Blackwell et al., 2005). Determination of the actigraphic, night-time rest interval (i.e., the period between Bed-time and Rise-time) is most highly correlated with polysomnography when Bed-time and Rise-time are determined by visually examining the actogram and using the sleep diary to aid interpretation (Boyne, Sherry, Gallagher, Olsen, & Brooks, 2013). "

    Neuropsychological Rehabilitation 08/2015; DOI:10.1080/09602011.2015.1074590 · 1.96 Impact Factor
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    • "Participants were asked to complete a diary while wearing the actigraph; the sleep diary data were used to edit and score the actigraph data. The protocol, which was very similar to that in the Study of Osteoporotic Fractures, has been described previously (Blackwell et al., 2005). Each diary included data on time in and out of bed, estimated time when participants fell asleep and awoke, the number of times they thought they woke during the night, information about naps, time and reasons for removing the actigraph, and times the participants were inactive for long durations as when watching television or movies. "
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    ABSTRACT: This study examined the association between race/ethnicity and objectively measured sleep characteristics in a large sample of older men. Black men had significantly shorter total sleep time (6.1 hr vs. 6.4 hr), longer sleep latency (28.7 min vs. 21.9 min), lower sleep efficiency (80.6% vs. 83.4%), and less slow-wave sleep (4.9% vs. 8.8%) than White men, even after controlling for social status, comorbidities, body mass index, and sleep-disordered breathing. Hispanic men slept longer (6.7 hr) at night than Black (6.1 hr) and Asian American men (6.1 hr). This study supports significant variations in sleep characteristics in older men by race/ethnicity.
    Behavioral Sleep Medicine 12/2011; 10(1):54-69. DOI:10.1080/15402002.2012.636276 · 2.34 Impact Factor
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    • "The average of the sleep parameters over all nights was used in this analysis to minimize interdaily variability. In general, scoring of actigraphy data was very reliable and highly predictive of total sleep time as measured by PSG [33]. "
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    ABSTRACT: Sleep disturbance and insomnia are commonly reported by postmenopausal women. However, the relationship between hormone therapy (HT) and sleep disturbances in postmenopausal community-dwelling adults is understudied. Using data from the multicenter Study of Osteoporotic Fractures (SOF), we tested the relationship between HT and sleep-wake estimated from actigraphy. Sleep-wake was ascertained by wrist actigraphy in 3,123 women aged 84 +/- 4 years (range 77-99) from the Study of Osteoporotic Fractures (SOF). This sample represents 30% of the original SOF study and 64% of participants seen at this visit. Data were collected for a mean of 4 consecutive 24-hour periods. Sleep parameters measured objectively included total sleep time, sleep efficiency (SE), sleep latency, wake after sleep onset (WASO), and nap time. All analyses were adjusted for potential confounders (age, clinic site, race, BMI, cognitive function, physical activity, depression, anxiety, education, marital status, age at menopause, alcohol use, prior hysterectomy, and medical conditions). Actigraphy measurements were available for 424 current, 1,289 past, and 1,410 never users of HT. Women currently using HT had a shorter WASO time (76 vs. 82 minutes, P = 0.03) and fewer long-wake (> or = 5 minutes) episodes (6.5 vs. 7.1, P = 0.004) than never users. Past HT users had longer total sleep time than never users (413 vs. 403 minutes, P = 0.002). Women who never used HT had elevated odds of SE <70% (OR,1.37;95%CI,0.98-1.92) and significantly higher odds of WASO > or = 90 minutes (OR,1.37;95%CI,1.02-1.83) and > or = 8 long-wake episodes (OR,1.58;95%CI,1.18-2.12) when compared to current HT users. Postmenopausal women currently using HT had improved sleep quality for two out of five objective measures: shorter WASO and fewer long-wake episodes. The mechanism behind these associations is not clear. For postmenopausal women, starting HT use should be considered carefully in balance with other risks since the vascular side-effects of hormone replacement may exceed its beneficial effects on sleep.
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