Description

The Illness Attitudes Questionnaire (IAQ-29) is a psychometric instrument developed to assess individuals’ attitudes, beliefs, fears, and concerns regarding illness, health, medical care, and bodily symptoms. Originally developed by Richard Kellner, the questionnaire was designed to evaluate illness behavior and health anxiety, particularly characteristics associated with hypochondriasis (currently conceptualized as Illness Anxiety Disorder). Over time, the IAQ has become one of the most widely used instruments for investigating dysfunctional health-related beliefs and behaviors in both clinical and non-clinical populations.

The IAQ-29 examines multiple dimensions of illness attitudes, including excessive concern about developing serious diseases, fear of pain and death, abnormal health-related beliefs, disease conviction, bodily preoccupation, and healthcare-seeking or healthcare-avoidance behaviors. By providing a comprehensive assessment of illness-related cognitions and behaviors, the questionnaire contributes to understanding how individuals perceive, interpret, and respond to health-related experiences.

Analysis and Use of Data

The analysis of the IAQ-29 focuses on identifying patterns of health anxiety and maladaptive illness-related beliefs. Participants respond to 29 items that assess emotional, cognitive, and behavioral reactions toward illness and healthcare.

The questionnaire evaluates several dimensions of illness attitudes, including health anxiety, disease conviction, fear of illness, concern about pain, bodily preoccupation, treatment experiences, and attitudes toward medical care. The resulting data can be used to investigate associations between illness attitudes and psychological variables such as anxiety, depression, stress, obsessive-compulsive symptoms, somatization, quality of life, coping strategies, and healthcare utilization.

Psychometric evaluation of the IAQ-29 generally includes the assessment of internal consistency using Cronbach’s alpha, test–retest reliability, and construct validity through exploratory or confirmatory factor analysis. Convergent and discriminant validity are commonly examined by comparing IAQ-29 scores with other established measures of health anxiety, illness behavior, somatic symptom severity, and emotional distress.

Objective

The primary objective of the IAQ-29 is to provide a reliable and valid assessment of attitudes, fears, and beliefs related to illness and health. Specifically, the questionnaire aims to:

  • Assess concerns and fears associated with physical illness and bodily symptoms.
  • Identify maladaptive illness beliefs and excessive health-related anxiety.
  • Evaluate illness behavior in both clinical and community populations.
  • Support the clinical assessment of individuals presenting with health anxiety or psychosomatic complaints.
  • Facilitate research examining the psychological, behavioral, and cognitive factors associated with illness perceptions and healthcare utilization.

Scoring

The IAQ-29 consists of 29 items rated using a Likert-type response scale, according to the instructions accompanying the instrument.

Total scores are obtained by summing the responses across all items, while subscale scores may also be calculated depending on the scoring procedure adopted. Higher scores indicate greater illness concern, stronger health anxiety, increased disease conviction, and more maladaptive illness-related beliefs and behaviors. Lower scores reflect more adaptive attitudes toward health and illness and lower levels of health-related psychological distress.

For research purposes, it is recommended that the instrument’s psychometric properties be evaluated by calculating Cronbach’s alpha, examining test–retest reliability, and confirming its factorial structure through exploratory or confirmatory factor analysis.

Applications

The Illness Attitudes Questionnaire is widely used in clinical psychology, psychiatry, psychosomatic medicine, behavioral medicine, and health psychology. It is particularly valuable for identifying individuals with elevated health anxiety, illness-related fears, or dysfunctional health beliefs that may contribute to excessive healthcare utilization or avoidance of medical care.

The IAQ-29 has been applied in studies investigating illness anxiety disorder, somatic symptom disorder, chronic illness adjustment, medical decision-making, quality of life, stress, depression, anxiety disorders, and psychosomatic conditions. It is also frequently employed to evaluate the effectiveness of psychological and cognitive-behavioral interventions targeting maladaptive illness beliefs and health anxiety.

References

Kellner, R., & Sheffield, P. (1982). Reliability and validity of the Illness Attitudes Questionnaire. Journal of Clinical Psychology, 38(4), 724–729.

Hiller, W., & Fichter, M. M. (1991). The Illness Attitudes Questionnaire: Validity and psychometric properties. Psychological Medicine, 21(3), 659–665.

Kellner, R. (1986). The Illness Attitudes Questionnaire: A Scale to Measure Illness Behavior. Journal of Psychosomatic Research, 30(1), 81–90.