|Reference code: ||PT/FB/BL-2014-234.03|
|The composite scale of morningness for chronotype estimation in Portuguese older adults: Psychometric properties and cutoff scores|
|Publication year: ||2019|
Chronotype refers to the individual differences that exist in the timing of circadian rhythms (e.g., core body temperature, sleep-wake cycle). The Composite Scale of Morningness (CSM) is one of the most widely used measures to estimate chronotype. Despite the importance of accurate chronotype assessments, the psychometric properties of the CSM are not sufficiently explored in older adults. The aim of this study was to examine reliability and validity data of the Portuguese version of the CSM, and to obtain cut-off points (based on percentiles), with a sample of older adults.
MATERIALS AND METHODS:
The sample comprised 522 participants (55% women) with ages between 65 and 95 years (M = 71.40; SD = 5.69), and up to 19 years of formal education (M = 7.10; SD = 4.56). After providing informed consent, all participants completed the CSM. So as to obtain validity data, participants also completed the Basic Scale on Insomnia symptoms and Quality of Sleep (BaSIQS), and questions concerning sleep schedules, and based on the latter the formula of the Mean Sleep point on Free days - sleep corrected (MSFsc) was used to estimate chronotype.
Regarding the scale's reliability, an alpha value of 0.81 was obtained. All items appeared to contribute to the scale's internal consistency, as removing items would reduce Cronbach's Alpha. The corrected item-total correlations assumed appropriate values (0.33 - 0.60). CSM scores showed a normal distribution, ranging from 19 to 54, M=39.06 (SD = 6.18). Concerning the scale's validity, a non-significant correlation (r = -0.07; p = 0.25) was observed between CSM scores and BaSIQS scores (discriminant validity). Significant correlations were obtained between CSM scores and sleep schedule variables (convergent validity), ranging between -0.34 and -0.79 (i.e., higher morningness scores were accompanied by earlier sleep-wake schedules), and between CSM scores and MSFsc, r = -0.532, p < 0.001. Cut-off points based on P10, P25, P75, and P90, were obtained.
The Portuguese version of the CSM seems to be a valid and reliable measure for chronotype assessment in older adults. Internal consistency analyses suggest that the CSM is a consistent and homogeneous scale in this age group. Validity analyses revealed that the CSM significantly correlates with measures of related constructs (sleep schedules and mid sleep point), whilst presenting a non-significant correlation with a measure of a less related construct (sleep quality). CSM mean scores and cut-off scores were higher than those generally reported for young adults in agreement with the advancing circadian system phase with age.
|Accessibility: ||Document exists in file|
|Secondary author(s): |
|Gomes, A., Pires, L., Russo, B., Leitão, J.|
|Document type: |
|Number of reproductions: |
|Buekenhout, I., Gomes, A., Pires, L., Russo, B., & Leitão, J. (2019). The composite scale of morningness for chronotype estimation in Portuguese older adults: Psychometric properties and cutoff scores. Sleep Medicine, 64 (Suppl. 1), S8-S9.|
|Indexed document: ||Yes|
|Keywords: ||Chronotype. / Scale / Psychometric properties |