| MEASUREMENT PROPERTIES | |
| Limitations | |
| Observations |
The recall period for items is at least three times per week during the last month, which corresponds to criterion B of the ICD-10 for insomnia. |
| 1. RELIABILITY | |
| A. Internal Consistency | Tested |
| Cronbach's (Describe) |
Cronbach’s α was 0.87 (AIS-5) to 0.89 (AIS-8) in the original cohort |
| B. Reliability intraobserver or test-retest | Tested |
| Continuous scores: intraclass correlation coefficient (ICC) Dichotomus: Cohen kappa (Describe) |
Pearson’s correlation coefficient was 0.88 (AIS-5) to 0.89 (AIS-8) for questionnaires administered 1 week apart. For a longer period of test-retest reliability at a mean of 81 days in a chronic pain population, the ICC was 0.64 for the AIS-8 |
| C. Reliability interobserver or Measurement error | Not Tested |
| Standard error of measurement (SEM), smallest detectable change (SDC) or Limits of agreement (LoA) (Describe) |
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| 2. VALIDITY | |
| A. Content validity: face validity | Tested |
| Expert opinion (relevance and comprehensiveness) (Describe) |
The AIS has high face validity because the items match ICD-10 criteria for nonorganic insomnia. Notably, the International Classification of Sleep Disorders, version 3 (ICSD-3) does not differentiate between organic, nonorganic, or other subtypes of insomnia (except acute or chronic) and has different diagnostic criteria compared with ICD10. The DSM-5 similarly removed the distinction between primary and secondary insomnia and has different diagnostic criteria compared with ICD-10. Because the ICSD-3 and DSM-5 are used more widely in sleep medicine, the face validity of the AIS may be decreased, compared with these updated diagnostic criteria |
| B. Construct Validity: Structural validity |
Not Tested |
| Hypotheses-testing | Tested |
| Cross-cultural validity | Tested |
| Brief Description | |
| C. Criterion validity | Tested |
| Comparison with a 'gold standard' Continuous scores: correlations, ROC curves Dichotomus: Sensitivity & Specificity (Describe) |
Using a cutoff of 6 or higher, the AIS-8 distinguished individuals with insomnia from those without insomnia with a sensitivity of 93% and specificity of 85% in the original validation cohort. The original validation cohort consisted of 176 individuals with insomnia and 123 individuals without insomnia who were diagnosed according to a nonstructured clinical interview, with the diagnosis based on ICD-10 criteria. This cohort was composed of 105 patients presenting to a primary health clinic with a complaint of insomnia without an obvious cause, 144 psychiatric patients, and 50 nonpatient controls. |