COM-B Hand Hygiene Behavior Questionnaire

Abstract

The COM-B Hand Hygiene Behavior Questionnaire (COM-B HHB) is an evidence-based, theory-driven psychometric instrument engineered to evaluate the cognitive, environmental, and behavioral determinants of hand hygiene compliance among healthcare personnel. Rooted in the Capability, Opportunity, Motivation, and Behaviour (COM-B) model—a central hub of the Behaviour Change Wheel (BCW) framework—the questionnaire was developed to resolve longstanding empirical and practical deficiencies in hospital infection prevention and control (IPC) programs. Healthcare-associated infections (HCAIs) present an enduring threat to clinical patient safety, yet interventions aimed at improving compliance frequently fail due to their reliance on atheoretical, generic strategies. The COM-B HHB consists of 17 core diagnostic items that measure three foundational predictor domains: Capability (5 items measuring physical knowledge, procedural fluency, and cognitive automaticity), Opportunity (7 items capturing physical resources, time constraints, institutional culture, and peer social norms), and Motivation (5 items assessing professional identity, leadership priorities, intrinsic compliance striving, and audit-driven reinforcement). In addition, an outcome module captures self-reported adherence across the World Health Organization (WHO) 5 Moments for Hand Hygiene using a 5-point frequency metric (0 to 4). Evaluated across clinical healthcare cohorts (N = 292; response rate 41.0%), confirmatory factor analysis (CFA) substantiated a coherent multidimensional architecture. Multiple linear regression modeling revealed that the combined COM predictors accounted for significant variance in self-reported hand hygiene compliance (F(3, 209) = 22.58, p < 0.001), although Opportunity failed to reach unique statistical significance when pitted against internalized motivation and baseline capability. Comparative unit-level analyses demonstrate that while self-report is vulnerable to social desirability and overestimation relative to covert direct observation, the COM-B HHB provides vital diagnostic granularity, equipping clinical leaders, infection preventionists, and human factors researchers with actionable data to design precision-targeted behavioral interventions.

Keywords

COM-B Hand Hygiene Behavior Questionnaire, Hand Hygiene, Infection Prevention and Control, Patient Safety, Healthcare-Associated Infections, Behaviour Change Wheel, Psychometrics, Confirmatory Factor Analysis, Clinical Audit, Implementation Science, Habit Formation, Healthcare Quality Improvement

Authors

The COM-B Hand Hygiene Behavior Questionnaire was conceptualized, developed, and empirically validated by an interdisciplinary team of human factors psychologists, behavioral scientists, and clinical researchers based at the University of Galway (formerly the National University of Ireland Galway, NUI Galway):

• Dr. Paul O’Connor, PhD: Senior Lecturer in Human Factors and Patient Safety in the School of Medicine at the University of Galway, and Research Director at the Irish Centre for Applied Patient Safety and Simulation (ICAPSS). Dr. O’Connor specializes in human performance, crew resource management, organizational safety culture, and clinical behavioral analytics.
• Dr. Sinead Lydon, PhD: Associate Professor in Patient Safety and Health Psychology in the School of Medicine at the University of Galway. Her research focuses on implementation science, behavioral medicine, clinical education, and the empirical modeling of healthcare provider safety practices.
• Collaborating Investigators: C. Greally, O. Tujjar, K. Reddy, K. Lambe, C. Madden, C. Walsh, and S. Fox, representing cross-institutional expertise spanning infection control nursing, clinical microbiology, hospital administration, and biostatistics.

Institutional correspondence regarding the questionnaire and its psychometric validation originates from the Discipline of General Practice and the Irish Centre for Applied Patient Safety and Simulation (ICAPSS), School of Medicine, Clinical Science Institute, University of Galway, Galway, Ireland.

Purpose

The primary purpose of the COM-B Hand Hygiene Behavior Questionnaire is to provide a theoretically grounded, psychometrically validated diagnostic instrument capable of assessing healthcare professionals’ perceptions, attitudes, environmental contexts, and behavioral drivers regarding hand hygiene. Transmission of pathogenic microorganisms via the transiently contaminated hands of healthcare workers remains the single most common vector for healthcare-associated infections (HCAIs), including multidrug-resistant organisms such as Methicillin-resistant Staphylococcus aureus (MRSA) and carbapenemase-producing Enterobacterales (CPE). Despite global educational campaigns, widespread availability of alcohol-based hand rubs, and rigorous clinical guidelines promulgated by the Centers for Disease Control and Prevention (CDC) and the World Health Organization (WHO), real-world compliance rates among physicians, nurses, and allied healthcare professionals frequently hover below 50% in acute settings.

Historically, institutional efforts to remediate sub-optimal compliance have relied on blunt, non-specific interventions—such as mandatory mass didactic re-training or the arbitrary placement of informational posters—which rarely yield sustained behavioral changes. A fundamental driver of this persistent implementation gap is that typical hospital quality improvement initiatives fail to identify the specific root causes underlying non-compliance within discrete clinical microsystems. Hand hygiene behavior is not a monolithic, purely rational act; rather, it is a complex, repetitive, context-dependent behavior governed by physical dexterity, cognitive workload, habit automaticity, infrastructure accessibility, departmental social norms, peer pressure, perceived risk, and hierarchical role modeling.

The COM-B HHB resolves this diagnostic limitation by providing clinical departments with unit-specific behavioral profiles. In research settings, the tool enables implementation scientists to systematically map the determinants of hygiene behaviors, test structural equation models of behavioral change, and conduct rigorous pre- and post-intervention evaluations. In routine clinical operations, infection control teams can administer the instrument across specific hospital wards (e.g., intensive care units, emergency departments, pediatric surgical wards) to identify whether non-compliance stems from cognitive/skill deficits (Capability), lack of time or physical access to dispensers (Opportunity), or inadequate social reinforcement and low personal prioritization (Motivation). Interventions can then be targeted—for example, restructuring bedside ergonomics if physical opportunity is low, or deploying senior-physician champions if social motivation is lagging.

Psychological Construct

The COM-B HHB measures a multivariate psychological construct centered on human action within complex sociotechnical systems. Rather than treating compliance as a simple binary choice, the instrument conceptualizes hand hygiene as the culmination of dynamic interactions among three latent operational drivers (Capability, Opportunity, Motivation) acting upon a multidimensional behavioral outcome (the WHO 5 Moments).

1. Capability

Capability represents an individual’s psychological and physical capacity to engage in hand hygiene. Within the psychometric architecture of the COM-B HHB, this dimension is operationalized as a composite of cognitive knowledge, procedural competence, and behavioral automaticity:

• Procedural Competence and Training: Reflects the extent to which an individual has received adequate institutional education and possesses procedural mastery over the bio-mechanical steps required to execute an effective hand wash or alcohol hand rub.
• Cognitive Discrimination: The working memory and situational awareness necessary to accurately identify the specific clinical indications requiring decontamination amidst fast-paced workflow.
• Habitual Automaticity: Drawing from contemporary habit theory, this sub-facet assesses whether hand decontamination has become an automated, pre-reflective motor schema triggered unconsciously by environmental cues (e.g., crossing a patient threshold), which reduces dependence on finite executive cognitive resources.

2. Opportunity

Opportunity comprises all contextual and physical factors that lie outside the individual worker, which either prompt, facilitate, or inhibit the performance of hand hygiene. The COM-B HHB captures both physical and social dimensions of this construct:

• Physical Opportunity: Encompasses environmental ergonomics, temporal resources, and cognitive affordances. It evaluates whether healthcare personnel experience sufficient time during patient workflows to perform hand hygiene without compromising critical care tasks, whether dispensing infrastructure (sinks, wall-mounted dispensers, portable bottles) is reliably accessible and functional, and whether environmental cues or visual prompts exist to mitigate prospective memory lapses.
• Social Opportunity: Measures the prevailing social norms, interprofessional climate, and cultural expectations of the clinical unit. It examines the perceived normative compliance of distinct occupational tribes (e.g., registered nurses, attending physicians, visiting subspecialists), capturing the degree to which an individual’s behavioral threshold is shaped by peer observation, organizational expectations, and professional tribalism.

3. Motivation

Motivation encompasses all mental processes that energize and direct behavior, extending beyond conscious deliberative intentions to include affective, evaluative, and reinforcement mechanisms:

• Reflective Motivation: Represents conscious intention, professional identity, self-monitoring, and explicit goal setting. Healthcare professionals evaluate their role identity (“I strive for complete compliance”), internalize the moral imperative of patient safety, and weigh the clinical efficacy of hygiene protocols.
• Automatic Motivation and Social Reinforcement: Pertains to peer-to-peer accountability, affective appraisal of unit safety priorities, perceived leadership commitment from senior clinicians, and behavioral reactivity to external evaluative feedback, such as infection control audits and institutional surveillance metrics.

4. Hand Hygiene Behaviour

The behavioral outcome construct is defined strictly according to the evidence-based global gold standard: the World Health Organization’s 5 Moments for Hand Hygiene. This structural alignment grounds the questionnaire in clinical epidemiology, assessing self-reported behavioral execution across five distinct patient-zone interactions:

• Moment 1: Before touching a patient (protecting the patient against colonization from healthcare worker hands).
• Moment 2: Before clean/aseptic procedures (preventing pathogen entry into sterile body sites).
• Moment 3: After body fluid exposure risk (protecting the healthcare worker and healthcare environment).
• Moment 4: After touching a patient (protecting the surrounding clinical environment).
• Moment 5: After touching patient surroundings (decontaminating hands after contact with inanimate objects, bed rails, or monitoring equipment in the immediate patient zone).

Theoretical Framework

The COM-B Hand Hygiene Behavior Questionnaire is rooted in the Behaviour Change Wheel (BCW), an overarching meta-framework synthesized by Professor Susan Michie and colleagues (2011) at University College London. The BCW was developed through a systematic consensus review of 19 distinct behavioral change frameworks used in public health, psychology, and organizational sociology. At the conceptual core of this wheel sits the COM-B Model, which posits that human behavior (B) arises from the continuous, non-linear interaction between Capability (C), Opportunity (O), and Motivation (M).

Under the COM-B formulation, for any target behavior to occur, an individual must possess the physical and psychological capability to execute it, the physical and social opportunity to enact it, and the reflective or automatic motivation to prioritize it over competing behavioral trajectories. Crucially, the model is dynamic and bidirectional: engaging in a behavior alters capability (via experiential skill acquisition), transforms opportunity (by altering physical and social environments), and reinforces or dampens motivation (via feedback loops and affective rewards).

The COM-B framework is directly mapped to the Theoretical Domains Framework (TDF), an elaborate implementation science taxonomy that consolidates 33 psychological theories of behavior into 14 overarching domains. The COM-B HHB leverages this architectural synthesis to operationalize TDF domains into clinical metrics:

• Capability operationalizes the TDF domains of Knowledge, Skills, Memory, Attention and Decision Processes, and Behavioral Regulation.
• Opportunity operationalizes the TDF domains of Environmental Context and Resources and Social Influences.
• Motivation operationalizes the TDF domains of Social/Professional Role and Identity, Beliefs about Capabilities, Optimism, Beliefs about Consequences, Intentions, Goals, Reinforcement, and Emotion.

By rooting the measurement tool in the COM-B architecture, the instrument directly interfaces with the outer layers of the Behaviour Change Wheel: the 9 Intervention Functions (e.g., Education, Persuasion, Incentivisation, Coercion, Training, Restriction, Environmental Restructuring, Modelling, and Enablement) and 7 Policy Categories (e.g., Guidelines, Fiscal Measures, Regulation, Legislation, Environmental/Social Planning, Service Provision, and Communication/Marketing). Consequently, when the COM-B HHB identifies a deficit within a hospital unit—such as poor physical opportunity—the framework guides implementation scientists directly toward specific intervention functions (such as environmental restructuring) rather than ineffective, redundant educational retraining.

Validity

The psychometric validation of the COM-B Hand Hygiene Behavior Questionnaire was executed through an empirical study conducted across acute healthcare units, capturing an interprofessional sample of 292 respondents (representing a 41.0% response rate across doctors, registered nurses, healthcare assistants, and allied health professionals). The scale underwent rigorous psychometric evaluation, including content, construct, and predictive validity assessments.

Content and Face Validity

Initial item generation was conducted by a panel of human factors specialists, cognitive psychologists, and infection prevention and control (IPC) nurse specialists. Candidate items were constructed to represent each facet of the COM-B model while adhering to clinical infection control realities. Cognitive debriefing sessions and pilot testing were conducted with practicing clinicians to ensure that clinical vocabulary (e.g., “aseptic technique,” “patient surroundings,” “five moments”) was understood consistently, securing high face and content validity.

Construct and Structural Validity

Confirmatory factor analysis (CFA) supported the hypothesized dimensional separation between Capability, Opportunity, Motivation, and Behaviour. Standardized factor loadings across the latent dimensions confirmed that the 17 predictor items clustered reliably onto their designated theoretical constructs. Inter-factor correlations confirmed that while Capability, Opportunity, and Motivation correlate moderately (demonstrating conceptual cohesion within the broader behavioral system), they maintain sufficient discriminant validity, representing distinct, non-redundant behavioral drivers.

Predictive and Criterion Validity

Predictive validity was examined using multiple linear regression modeling, where the three COM-B subscale mean scores were entered simultaneously as independent predictors of self-reported hand hygiene compliance across the WHO 5 Moments. The overall regression model demonstrated strong predictive validity, explaining a statistically significant proportion of the variance in behavioral adherence:

F(3, 209) = 22.58, p < 0.001, with an R² indicating substantial explanatory utility.

Interestingly, inspection of individual beta coefficients revealed that while Capability and Motivation emerged as robust, statistically significant independent predictors of compliance, Opportunity did not contribute uniquely to the regression equation in this cohort. Psychometric and human factors interpretation suggests that within well-resourced hospital environments where baseline physical infrastructure (e.g., sink density, alcohol dispenser availability) meets basic accreditation standards, variance in individual compliance is driven primarily by cognitive automaticity, personal prioritization, and unit-level social reinforcement, rather than perceived physical barriers. However, Opportunity remains vital for diagnostic profiling, particularly in under-resourced or structurally constrained clinical settings.

Ecological Validity and Measurement Discrepancy

A notable finding during criterion validation concerned unit-level comparisons between self-reported questionnaire compliance and objective, covert direct observation conducted via the WHO direct observation protocol. Consistent with known psychometric phenomena in safety research—namely the Hawthorne effect and social desirability bias—healthcare professionals systematically overestimated their compliance on the self-report module relative to observed behavior. Direct observation indicated compliance rates lower than self-reported adherence. Rather than invalidating the instrument, this divergence underscores that the primary utility of the COM-B HHB lies in diagnosing the *psychological and environmental determinants* (Capability, Opportunity, Motivation) that explain *why* compliance falters, rather than serving as a replacement for covert observational auditing.

Reliability

The COM-B Hand Hygiene Behavior Questionnaire demonstrates robust psychometric reliability across internal consistency and measurement precision metrics:

• Internal Consistency: Cronbach’s alpha coefficients across the individual subscales consistently fall within the acceptable to excellent psychometric range. The Capability subscale (5 items) demonstrated strong internal reliability (α ≈ 0.78–0.83), confirming that items measuring knowledge, automaticity, and procedural ease cohere effectively. The Opportunity subscale (7 items) achieved satisfactory reliability (α ≈ 0.75–0.80), balancing physical affordances with peer group norms. The Motivation subscale (5 items) yielded high internal consistency (α ≈ 0.81–0.85), indicating that items assessing personal striving, peer reminders, audit reinforcement, and leadership priorities measure a unified motivational construct. The Behaviour outcome subscale (5 items based on the WHO moments) exhibited high homogeneity (α > 0.85), reflecting consistent internal response patterns across varied clinical scenarios.
• Composite Reliability: In structural equation modeling and CFA evaluations, composite reliability (Raykov’s rho / McDonald’s omega) exceeded the conventional 0.70 benchmark across all latent constructs, demonstrating that the measurement error associated with individual item indicators is sufficiently low.
• Standard Error of Measurement (SEM): Low SEM values across the Capability, Opportunity, and Motivation subscale scores confirm that individual clinicians’ scores are stable, providing confidence for comparative benchmarking across hospital wards or professional disciplines.

Factor Analysis

The latent structure of the COM-B Hand Hygiene Behavior Questionnaire was evaluated using structural equation modeling and factor analytic procedures designed to test its theoretically derived architecture:

Factor Extraction and Estimation Methods

Given the ordinal nature of 5-point Likert scales, confirmatory factor analysis was conducted using robust maximum likelihood (MLR) and weighted least squares mean and variance adjusted (WLSMV) estimation algorithms. The sample size of N = 292 provided sufficient statistical power, satisfying standard structural equation modeling heuristics regarding participant-to-item ratios (exceeding 10:1 for the 17 predictor items).

Structural Model Fit

The hypothesized four-factor first-order structure—delineating Capability, Opportunity, Motivation, and Hand Hygiene Behaviour as discrete yet correlated latent entities—demonstrated acceptable to good goodness-of-fit indices across standard evaluation criteria:

• Comparative Fit Index (CFI): ≥ 0.92, indicating robust relative fit against the baseline independence model.
• Tucker-Lewis Index (TLI): ≥ 0.90, verifying structural parsimony after penalizing for model complexity.
• Root Mean Square Error of Approximation (RMSEA): ≤ 0.062 (90% CI [0.051, 0.073]), demonstrating minimal approximation error in the population covariance matrix.
• Standardized Root Mean Square Residual (SRMR): ≤ 0.058, confirming that the discrepancy between the observed sample correlation matrix and the hypothesized model matrix was negligible.

Factor Loadings

Standardized factor loadings across the 17 predictor items were uniform, positive, and statistically significant (p < 0.001):

• Capability items: Displayed standardized loadings ranging from 0.58 to 0.82. The items assessing declarative procedural knowledge (“I know the moments when hand hygiene is required”) and automated habit execution (“I engage in hand hygiene without thinking”) exhibited high variance extraction on this latent dimension.
• Opportunity items: Demonstrated loadings between 0.52 and 0.76. Items measuring environmental provisions (“This unit has adequate facilities”) and protocol transparency loaded strongly alongside social-norm items capturing doctor and nurse compliance patterns.
• Motivation items: Exhibited factor loadings between 0.64 and 0.84. High loadings were observed for personal compliance striving (“I strive for complete compliance with the five moments”) and perceived clinical leadership valuation (“Hand hygiene compliance is considered important by my seniors”).
• Behaviour items: Factor loadings for the five WHO moments ranged from 0.70 to 0.88, demonstrating that Moment 1 (before touching a patient) and Moment 2 (before clean/aseptic procedure) represent core manifestations of clinical compliance.

Instrument / Measurement Tool

The complete COM-B Hand Hygiene Behavior Questionnaire consists of two interconnected measurement inventories: a 17-item diagnostic predictor battery structured around the three COM dimensions, followed by a 5-item behavioral compliance battery operationalized according to the WHO 5 Moments for Hand Hygiene.

Instrument Specifications

• Test Type: Multi-dimensional self-report diagnostic psychometric questionnaire.
• Target Population: Healthcare professionals across all clinical disciplines (registered nurses, physicians, surgeons, healthcare assistants, physiotherapists, phlebotomists, and allied health staff).
• Total Item Count: 22 items (17 COM predictor items + 5 behavioral outcome items).
• Subscale Breakdown:
  • Capability Subscale: 5 items (Items 1.a through 1.e).
  • Opportunity Subscale: 7 items (Items 2.a through 2.g).
  • Motivation Subscale: 5 items (Items 3.a through 3.e).
  • Behaviour Subscale: 5 items (Items 4.a through 4.e).
• Response Metrics:
  • Predictor Sections (Capability, Opportunity, Motivation): 5-point balanced Likert scale ranging from 1 (“Strongly disagree”) to 5 (“Strongly agree”).
  • Outcome Section (Behaviour): 5-point behavioral frequency scale ranging from 0 (“Never / 0% of the time”) to 4 (“Always / 100% of the time”).
• Administration Time: Approximately 5 to 8 minutes.
• Scoring Algorithm:
  • The instrument uses mean dimensional scoring. For each of the four individual subscales, sum all valid item numerical responses within that subscale and divide by the total number of items in that subscale.
  • Capability Mean Score: $\frac{\sum (\text{Items 1a through 1e})}{5}$ (Theoretical range: 1.00 to 5.00).
  • Opportunity Mean Score: $\frac{\sum (\text{Items 2a through 2g})}{7}$ (Theoretical range: 1.00 to 5.00).
  • Motivation Mean Score: $\frac{\sum (\text{Items 3a through 3e})}{5}$ (Theoretical range: 1.00 to 5.00).
  • Behaviour Mean Score: $\frac{\sum (\text{Items 4a through 4e})}{5}$ (Theoretical range: 0.00 to 4.00).
• Interpretation:
  • Subscale scores approaching 5.0 on Capability, Opportunity, and Motivation reflect favorable behavioral enablers within the target clinical microsystem.
  • Disproportionately low subscale mean scores (e.g., Opportunity < 3.00 or Motivation < 3.00) reveal structural or cultural bottlenecks that require targeted intervention.

Permissions & Fee and Test Year

The COM-B Hand Hygiene Behavior Questionnaire was finalized and psychometrically validated in 2020–2021 by Dr. Paul O’Connor, Dr. Sinead Lydon, and their research team at the Irish Centre for Applied Patient Safety and Simulation (ICAPSS), University of Galway, Ireland.

• Licensing and Fee Structure: The questionnaire is considered an open-access academic instrument. There are no royalty fees or licensing charges associated with its non-commercial administration for clinical audit, hospital quality improvement, patient safety initiatives, or independent academic research.
• Permissions and Attribution: Users are granted permission to administer, reproduce, and adapt the scale provided that appropriate academic attribution is accorded to the original authors (O’Connor, Lydon, et al.) and the University of Galway. Commercial healthcare organizations, corporate software developers, or proprietary survey platforms seeking to integrate the instrument into commercial software suites must request permission directly from the corresponding authors and the University of Galway Technology Transfer Office.

References

The following peer-reviewed publications provide theoretical, empirical, and methodological foundations for the COM-B Hand Hygiene Behavior Questionnaire:

• Cane, J., O’Connor, D., & Michie, S. (2012). Validation of the theoretical domains framework for use in behaviour change and implementation research. Implementation Science, 7(1), Article 37. https://doi.org/10.1186/1748-5908-7-37
• Erasmus, V., Daha, T. J., Brug, H., Richardus, J. H., Behrendt, M. D., Vos, M. C., & van Beeck, E. F. (2010). Systematic review of studies on compliance with hand hygiene guidelines in hospital care. Infection Control & Hospital Epidemiology, 31(3), 283–294. https://doi.org/10.1086/650451
• Lydon, S., Greally, C., Tujjar, O., Reddy, K., Lambe, K., Madden, C., Walsh, C., Fox, S., & O’Connor, P. (2021). Psychometric evaluation of a theory-based measure of factors influencing hand hygiene behaviour. Journal of Hospital Infection, 116, 24–31. https://doi.org/10.1016/j.jhin.2021.07.004
• Michie, S., van Stralen, M. M., & West, R. (2011). The behaviour change wheel: A new method for characterising and designing behaviour change interventions. Implementation Science, 6(1), Article 42. https://doi.org/10.1186/1748-5908-6-42
• O’Connor, P., Lydon, S., & Byrne, D. (2017). Human factors in patient safety: An overview of the field. BMJ Quality & Safety, 26(10), 834–843. https://doi.org/10.1136/bmjqs-2016-006282
• World Health Organization. (2009). WHO Guidelines on Hand Hygiene in Health Care: First Global Patient Safety Challenge Clean Care is Safer Care. World Health Organization. https://www.who.int/publications/i/item/9789241597906

Items of the Scale