An evaluation of the Circadian Type Questionnaire

Validation of the 6-item Evening Chronotype Scale (ECS): a modified version of Composite Scale Morningness

In a previous study comparing two representative chronotype questionnaires to screen for delayed sleep-phase disorder, six items from the simplified language version of Composite Scale of Morningness (CSM) have been found to be useful and effective for screening evening-type person. In this study, we reverse coded the six items from CSM and named them Evening Chronotype Scale (ECS). The primary aim of this study was to examine the psychometric properties, validity, and test-retest reliability of the ECS when administered on mood disorder patients. The secondary aim was to further examine the relationship between circadian preferences and symptoms of mood disorders. The study sample was of 472 mood disorder patients including major depressive disorder, bipolar disorder I, and bipolar disorder II. The 13-item full version CSM and 6-item ECS were externally validated by self-reported sleep time, wake time, sleep latency, depressive symptoms, hypomanic symptoms, quality of life, and impulsivity. Cronbach's alpha was calculated for the internal consistency of the ECS, and the test-retest reliability analysis was also performed. Our results suggest that the ECS is a reliable and valid instrument to assess circadian preference in mood disorder patients. First, the ECS showed moderate to good internal consistency (Cronbach's alpha = 0.727). Also, it showed external validity comparable to that of the 13-item CSM. Participants who were more evening-oriented according to the ECS slept and woke up later, took longer time to fall asleep, showed more depressive and hypomanic symptoms, and showed lower quality of life and higher impulsivity. As circadian rhythm disruption has been shown to affect the regulation of mood symptoms in patients with mood disorders, assessment of circadian preferences may be crucial in clinical settings. We suggest that ECS appears to be an easy-to-use instrument that is reliable and valid.

Reliability of the Spanish version of the Composite Scale of Morningness

Aim

The aim of this study was to examine the reliability of the Spanish version of Composite Scale of Morningness (CSM) and its ability to measure the circadian typology.

Subjects and methods

Voluntary and unpaid psychology students (N = 391; 132 men and 259 women), aged between 17 and 33, completed the questionnaire between the months of September and December.

Results

The total score was independent of age and gender, with a close to normal distribution and a non-significant negative skewness. The internal consistency was high (Cronbach’s α = 0.87) and factor analysis extracted three factors labeled Time of Retiring (items 2 and 7), Activity Planning (items 8, 9, and 13) and Morning Affect (items 3–6, and 10–12). With the 10th and 90th percentiles as cut-off scores, scorers below 22 (N = 40; 10.2%) are classified as evening-types and scorers above 39 as morning-types (N = 28; 7.2%).

Conclusion

The Spanish questionnaire shares most of the good psychometric properties of other versions of the CSM, and thus can be used for Spanish-speaking student samples. Nevertheless, further studies of normative data in workers and aged subjects are needed in order to validate CSM.

[Seven hour shifts versus 12 hours in intensive nursing care: going against the tide]

Working in shifts has an impact on the well being of health care professionals, affecting their quality of life. The main objective of this study is to describe the consequences of 12hours work shifts versus 7hours for nursing professionals working in intensive care units. A cost-sectional, descriptive study was conducted in two tertiary hospitals of Barcelona, these being the Hospital Clínico and Hospital Vall d'Hebron (of 7hour and 12hour shifts, respectively). The data was collected through a questionnaire having 29 closed questions that was anonymous and self-administered. The questionnaire was based on two scales: Standard Shiftwork Index and Shiftwork. locus of control. Data was processed through SPSS V.18.0. The target population consisted of 85 people, for whom 52 surveys were valid: 22 in Hospital Clínico of Barcelona and 30 in Hospital Vall d'Hebron. Professionals working a 12-hour shift express higher levels of work and family conciliation, especially in the case of leisure time to enjoy (×2: 10.635 p=0.031) and family-friends time dedication as well as lower levels of perceived fatigue. No differences were found between type of shift and ease of development of professional work, even though the 12-hour shift has higher levels.

Evaluation of two circadian rhythm questionnaires for screening for the delayed sleep phase disorder

OBJECTIVE

Delayed sleep phase disorder (DSPD) is a condition in which patients often fall asleep some hours after midnight and have difficulty waking up in the morning. Circadian chronotype questionnaires such as Horne-Östberg Morningness-Eveningness Questionnaire (MEQ) and Basic Language Morningness (BALM) scale have been used for screening for DSPD. This study was to evaluate these two chronotype questionnaires for screening of DSPD.

METHODS

The study samples were 444 DSPD and 438 controls. Cronbach's alpha coefficient was calculated to evaluate for internal consistency. An exploratory factor analysis was conducted using principal-axis factoring. The diagnostic performance of a test was evaluated using Receiver Operating Characteristic (ROC) curve analysis. A discriminant function analysis was also performed.

RESULTS

For internal consistency, Cronbach's alpha of 0.898 for BALM was higher than the 0.837 for MEQ, though both have acceptable internal consistency. BALM has better construct validity than the MEQ because some MEQ items measure different dimensions. However, when we evaluated the efficiency of two questionnaires for DSPD diagnosis by using the ROC curve, the BALM was similar to the MEQ. In a discriminant analysis with the BALM to classify the two groups (DSPD vs. normal), 6 items were identified that resulted in good classification accuracy. Upon examination of the classification procedure, 94.2% of the originally grouped cases were classified correctly.

CONCLUSION

These findings suggest that the BALM has better psychometric properties than the MEQ in screening and discriminating DSPS.

Transcultural properties of the composite scale of morningness: the relevance of the "morning affect" factor

Morningness scales have been translated into several languages, but a lack of normative data and methodological differences make cross-cultural comparisons difficult. This study examines the psychometric properties and factor structure of the Composite Scale of Morningness (CSM) in samples from five countries: France (n = 627), Italy (n = 702), Spain (n = 391), Thailand (n = 503), and Australia (n = 654). Strong national differences are identified. A quadratic relationship between age and CSM total score was apparent in the Australian data with a downward trend after age 35 yrs. There was no age effect in any sample in the range from 18 to 29 yrs. Factor analysis identified a three-factor solution in all groups for both men and women. Tucker's congruence coefficients indicate that: (1) this solution is highly congruent between sexes in each culture, and (2) a morning affect factor is highly congruent between cultures. These results indicate there are national differences in factorial structure and that cut-off scores used to categorize participants as morning- and evening-types should be established for different cultural and age groups.

The composite scale of morningness: further psychometric properties and temporal stability

OBJECT

To assess the temporal stability of the French version of the Composite Scale of Morningness (CSM), and to replicate our previous findings in an independent sample in order to confirm the good internal properties of this instrument.

METHOD

Sixty nursing students (11 males and 49 females) filled out the Composite Scale of Morningness on two occasions over a 13-month period.

RESULTS

The scale's reliability is high: Cronbach's alpha = 0.874 in males and 0.904 in females. The CSM total scores are normally distributed and independent of gender. They do not differ between occasions, and are highly correlated: r = +0.885 in males and r = +0.930 in females.

CONCLUSION

The French version of the CSM is stable over time and psychometrically reliable. These are the characteristics of a personality trait. Further studies should explore its personality, biological and genetic correlates.