Most cited article - PubMed ID 33269612
On Dimensionality, Measurement Invariance, and Suitability of Sum Scores for the PHQ-9 and the GAD-7
AIMS: To evaluate the psychometric properties of the Adelphi Adherence Questionnaire (ADAQ©) as an adherence measure in a diverse type 2 diabetes mellitus (T2DM) population in routine clinical practice. MATERIALS AND METHODS: Data were drawn from the Adelphi T2DM Disease Specific Programme™, a survey of physicians and adults with T2DM consulting in the United States, February-May 2021. Participants completed the ADAQ and single questions on medication satisfaction and convenience. Latent variable modelling (exploratory/confirmatory factor analyses, item response theory, Mokken scaling and bifactor analyses) assessed ADAQ dimensionality and composite scoring. Differential item functioning (DIF) analyses were conducted between participants taking injectable and non-injectable therapies, and with <3 or ≥3 long-term conditions. Correlational analyses with physician-reported adherence and compliance, and patient-reported treatment satisfaction, convenience and side-effects assessed construct validity. ADAQ scores by sociodemographic and clinical factors were also described. RESULTS: Overall, 1287 people with T2DM were included in this analysis (mean age 56.7 years [standard deviation: 12.8], 54.5% [n = 702] male). Latent variable modelling indicated a unidimensional reflective model fit, with a bifactor model confirming an 11-question essentially unidimensional composite score. Negligible DIF was found between groups. Cronbach's alpha and McDonald's omega were both ≥0.90. Moderate correlations with physician-reported adherence and compliance, and patient-reported medication convenience and satisfaction support construct validity. CONCLUSIONS: The ADAQ shows strong construct validity and high internal consistency reliability within a heterogenous T2DM population with negligible DIF between sub-groups. Future work should focus on test-retest reliability and detecting change over time.
- Keywords
- ADAQ, Adelphi adherence questionnaire, MLTC, T2DM, multiple long‐term conditions, psychometric evaluation,
- MeSH
- Medication Adherence * psychology MeSH
- Diabetes Mellitus, Type 2 * drug therapy psychology epidemiology MeSH
- Adult MeSH
- Hypoglycemic Agents * therapeutic use MeSH
- Middle Aged MeSH
- Humans MeSH
- Surveys and Questionnaires MeSH
- Psychometrics MeSH
- Reproducibility of Results MeSH
- Aged MeSH
- Patient Satisfaction MeSH
- Check Tag
- Adult MeSH
- Middle Aged MeSH
- Humans MeSH
- Male MeSH
- Aged MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
- Geographicals
- United States epidemiology MeSH
- Names of Substances
- Hypoglycemic Agents * MeSH
Anticipating clinical transitions in bipolar disorder (BD) is essential for the development of clinically actionable predictions. Our aim was to determine what is the earliest indicator of the onset of depressive symptoms in BD. We hypothesized that changes in activity would be the earliest indicator of future depressive symptoms. The study was a prospective, observational, contactless study. Participants were 127 outpatients with a primary diagnosis of BD, followed up for 12.6 (5.7) [(mean (SD)] months. They wore a smart ring continuously, which monitored their daily activity and sleep parameters. Participants were also asked to complete weekly self-ratings using the Patient Health Questionnaire (PHQ-9) and Altman Self-Rating Mania Scale (ASRS) scales. Primary outcome measures were depressive symptom onset detection metrics (i.e., accuracy, sensitivity, and specificity); and detection delay (in days), compared between self-rating scales and wearable data. Depressive symptoms were labeled as two or more consecutive weeks of total PHQ-9 > 10, and data-driven symptom onsets were detected using time-frequency spectral derivative spike detection (TF-SD2). Our results showed that day-to-day variability in the number of steps anticipated the onset of depressive symptoms 7.0 (9.0) (median (IQR)) days before they occurred, significantly earlier than the early prediction window provided by deep sleep duration (median (IQR), 4.0 (5.0) days; p <.05). Taken together, our results demonstrate that changes in activity were the earliest indicator of depressive symptoms in participants with BD. Transition to dynamic representations of behavioral phenomena in psychiatry may facilitate episode forecasting and individualized preventive interventions.
- Keywords
- Activity, Bipolar disorder, Densely-sampled, Mood variability, Onset, Sleep, Wearable technology,
- Publication type
- Journal Article MeSH
BACKGROUND: Medication non-adherence is a common issue in chronic illness. The World Health Organization has recognized a need for a valid and reliable method of measuring adherence to understand and mitigate non-adherence. This study aimed to psychometrically evaluate the English version of the Adelphi Adherence Questionnaire (ADAQ©), a questionnaire designed to assess patient-reported medication adherence across multiple therapy areas, in patients with Osteoarthritis (OA). METHODOLOGY: Data from the Adelphi OA Disease Specific Programme™, a survey of physicians and their consulting adult patients with OA conducted in the United States, November 2020 to March 2021, was used to assess the psychometric properties of the ADAQ. Patients completed the ADAQ, Adherence to Refills and Medication Scale (ARMS), Western Ontario and McMaster Universities Arthritis Index (WOMAC), and EQ-5D-3L. The measurement model of the 13-item ADAQ was assessed and refined using latent variable modelling (Multiple Indicator Multiple Cause, confirmatory and exploratory factor analyses, item response theory, Mokken scaling, and bifactor analyses). Correlational analyses (Spearman's rank and polyserial as appropriate) with ARMS, WOMAC, and EQ-5D-3L scores assessed construct validity. Anchor- and distribution-based analyses were performed to estimate between-group clinically important differences (CID). RESULTS: Overall, 723 patients were included in this analysis (54.5% female, 69.0% aged ≥ 60). Latent variable modelling indicated a unidimensional reflective model was appropriate, with a bifactor model confirming an 11-item essentially unidimensional score. Items 12 and 13 were excluded from scoring as they measured a different concept. The ADAQ had high internal reliability with omega hierarchical and Cronbach's alpha coefficients of 0.89 and 0.97, respectively. Convergent validity was supported by moderate correlations with items of the ARMS, and physician-reported adherence and compliance. Mean differences in ADAQ score between high and low adherence groups yielded CID estimates between 0.49 and 1.05 points, with a correlation-weighted average of 0.81 points. CONCLUSION: This scoring model showed strong construct validity and internal consistency reliability when assessing medication adherence in OA. Future work should focus on confirming validity across a range of disease areas.
- Keywords
- Adherence, PROs, Patient reported outcome development, Real-world evidence, Validity,
- MeSH
- Medication Adherence * psychology MeSH
- Adult MeSH
- Assessment of Medication Adherence * MeSH
- Middle Aged MeSH
- Humans MeSH
- Osteoarthritis * drug therapy psychology MeSH
- Surveys and Questionnaires MeSH
- Psychometrics * methods MeSH
- Reproducibility of Results MeSH
- Aged MeSH
- Check Tag
- Adult MeSH
- Middle Aged MeSH
- Humans MeSH
- Male MeSH
- Aged MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
- Geographicals
- United States MeSH