# The Bipolar Disorder Medication Adherence Battery: validity, reliability, and clinical benchmarks

## TL;DR

The study introduces a new tool to assess medication adherence in bipolar disorder patients, showing it is reliable and useful for clinical monitoring.

## Contribution

The BD-MAB is a novel, validated tool that comprehensively measures psychological and contextual factors influencing medication adherence in bipolar disorder.

## Key findings

- The BD-MAB demonstrated acceptable to excellent internal consistency across scales.
- The tool showed strong convergent and criterion validity when compared to serum medication levels and existing adherence measures.
- Clinically interpretable thresholds were established to detect meaningful changes in adherence behavior.

## Abstract

Medication adherence is pivotal in bipolar disorder, yet no tools assess the full range of psychological and contextual determinants that translate intention into behavior. This study developed and validated the Bipolar Disorder Medication Adherence Battery (BD-MAB) to support routine, measurement-based care.

The analytic sample comprised 167 adults with DSM-5 bipolar I disorder recruited from outpatient and inpatient services at a tertiary psychiatric hospital. Guided by the Integrated Behavioral Model, we mapped process measures—Attitude; Perceived norms (supportive, oppositional, pressuring, descriptive); Perceived control; Self-efficacy; Knowledge and skills; Environmental Constraints; Salience of Behavior; Habit; Intention and a behavior indicator. Psychometrics included internal consistency; construct validity via inter-construct correlations; convergent and discriminant validity with the Medication Adherence Rating Scale, Medication Adherence Report Scale, perceived social support, and quality of life; criterion validity against same-day serum medication levels; and distribution-based thresholds (standard error of measurement, critical change, minimally important difference, reliable change index).

Administered to euthymic adults with bipolar I disorder receiving mood stabilizers at a tertiary psychiatric hospital, the BD-MAB showed acceptable to excellent internal consistency across multi-item scales. Relations among constructs were theory-consistent, with intention aligning most closely with self-efficacy and attitudes, and the behavior indicator tracking intention. Concordance with serum levels supported criterion validity, and associations with an established adherence measure supported convergent validity. Clinically interpretable thresholds were derived to flag meaningful change for use in routine care.

The BD-MAB offers a comprehensive, clinically actionable assessment of adherence determinants and behavior in bipolar disorder, with initial evidence for reliability, validity, and practical change metrics to guide patient-level monitoring.