- Diseases and their treatment have an impact on patient well-being
- Quality of life (QoL) is a measure of an illness, disease and its treatment on patient welfare
- Has dimensions beyond physical measures of patients progress
- No universal definition of QoL exists
- It has three fundamental characteristics
- Multidimensional
- Physical - patients perceived ability to carryout daily activities
- Social - ability to interact with family and friends
- Psychological - degrees of depression, anxiety, fear etc
- Subjective
- Dynamic
Quality of life assessment
- QoL assessment is used to
- Access progress of individual patient
- In clinical trials to compare treatment options
- Determine cost-effectiveness of treatment
- Instrument used must be
- Valid - measure what it is supposed to measure
- Reliable - produce consistent results
- Responsive - be able to detect changes with time
- Can be either self-administered or by interview
- Can be repeated on several occasions
Measures of quality of life
- Data is usually collected using a structured questionnaire
- Different items tap various dimensions of QoL
- QoL instruments can be either generic or specific
Generic instruments
- Assess many dimensions
- Produce a global concept of QoL
- Two types of generic questionnaires exist
- Health profiles (e.g. SF-36)
- Health indices (e.g. Quality adjusted life years)
Specific instruments
- Used for specified disease or condition
- Several types exist
- Domain specific (e.g. Hospital anxiety and depression scales)
- Disease specific (e.g. EORTC QLQ-C30 for cancer patients)
- Population specific (e.g. children or elderly)
- Symptom specific (e.g. McGill pain questionnaire)
Bibliography
Cella D, Chang C H, Lai J S, Webster K. Advances in quality of life measurements in
oncology patients. Semin Oncol 2002; 29 (Suppl 8); 60-68.
Conroy T, Bleiberg H, Glimelius B. Quality of life in patients with advanced colorectal
cancer; what has been learnt? Eur J Cancer 2003; 39: 287-294 |