Functional Assessment of Cancer Therapy (FACT-G)

Abstract

The Functional Assessment of Cancer Therapy (FACT-G) is a core, general measure within the broader Functional Assessment of Chronic Illness Therapy (FACIT) measurement system. Developed by David F. Cella and colleagues in 1993, the FACT-G is a self-report instrument designed to evaluate the Quality of Life (QoL) in patients undergoing treatment for cancer. The scale assesses health-related quality of life (HRQoL) across four primary domains: Physical Well-being, Social/Family Well-being, Emotional Well-being, and Functional Well-being. Serving as a foundational tool, the FACT-G is frequently used in clinical trials and outcome studies to provide a comprehensive, patient-centered perspective on the impact of disease and therapy.

Keywords

FACT-G, Functional Assessment of Cancer Therapy, Quality of Life, HRQoL, Oncology, Cancer, Psychosocial Assessment, Functional Status, Patient Reported Outcomes (PROs).

Authors

David F. Cella, D.S. Tulsky, G. Gray, A.E. Bonomi, E.A. Hahn, S.R. Lloyd.

Purpose

The principal purpose of the Functional Assessment of Cancer Therapy (FACT-G) is to provide a standardized and reliable method for quantifying the multidimensional components of Health-Related Quality of Life (HRQoL) in adult patients with cancer. It is intended to be applicable across all cancer diagnoses and treatment phases, providing a consistent baseline measure that can be augmented by site-specific subscales (e.g., FACT-Lung, FACT-Breast) when necessary.

The instrument is utilized by researchers to measure treatment efficacy—specifically, the benefit of therapeutic interventions on a patient’s daily functioning and subjective well-being—and by clinicians for routine monitoring of patient distress and adjustment. By focusing on the past seven days, the FACT-G captures recent changes in status, making it sensitive to acute treatment effects and symptom management.

Construct

The FACT-G measures the construct of Health-Related Quality of Life (HRQoL), understood as the subjective impact of disease and treatment on an individual’s physical, psychological, and social functioning. This construct is operationalized through four distinct, yet correlated, domains of well-being, reflecting the holistic nature of cancer survivorship and palliative care.

The four fundamental dimensions assessed by the FACT-G are: Physical Well-being (PWB), covering symptoms like pain, nausea, and energy levels; Social/Family Well-being (SWB), addressing interpersonal relationships and support systems; Emotional Well-being (EWB), capturing mood states such as sadness, nervousness, and hope; and Functional Well-being (FWB), assessing the ability to work, enjoy life, and sleep well. Earlier versions (Version 3) also explicitly included a subscale for Relationship With Doctor (RWD), emphasizing the importance of communication in the treatment journey.

Validity

The validity of the FACT-G has been rigorously established through numerous studies since its inception. Construct validity is supported by confirmation that the subscales correlate logically with expected clinical variables; for instance, PWB scores are strongly associated with objective physical status measures, while EWB scores correlate highly with standardized depression and anxiety scales. Studies have confirmed that the instrument effectively discriminates between patient groups with differing performance statuses.

Content validity was ensured during the development phase by soliciting input from both oncology patients and expert clinicians, guaranteeing that the items adequately cover the spectrum of concerns relevant to HRQoL in cancer. Furthermore, the scale demonstrates excellent known-groups validity, consistently showing lower QoL scores in patients with advanced disease or those experiencing significant treatment toxicity.

Reliability

The Reliability of the FACT-G, a key measure in Psychometrics, is consistently high, particularly for the total score and most subscales, indicating stable and internally consistent measurement. Internal consistency is typically assessed using Cronbach’s alpha coefficients, with reported values generally meeting or exceeding acceptable clinical standards.

Reported Cronbach’s alpha ranges for the major subscales and total score include:

• Physical Well-Being (PWB): 0.65 – 0.82
• Social Well-Being (SWB): 0.55 – 0.75
• Relationship With Doctor (RWD): 0.40 – 0.75
• Emotional Well-Being (EWB): 0.66 – 0.84
• Functional Well-Being (FWB): 0.75 – 0.84
• Total Score (FACT-G): 0.82 – 0.90

The high coefficient for the Total FACT-G Score (0.82–0.90) confirms its strong internal consistency as a global measure of QoL. While the RWD and sometimes the SWB subscales may exhibit slightly lower coefficients, they are retained due to their clinical relevance in assessing holistic patient care and support.

Factor Analysis

The structure of the Functional Assessment of Cancer Therapy (FACT-G) is supported by confirmatory factor analysis (CFA), which validates the underlying multidimensional model. The scale is designed to load onto four primary, theoretically derived factors: Physical Well-being, Social/Family Well-being, Emotional Well-being, and Functional Well-being. This structure demonstrates that while the factors are related, they represent distinct components of the HRQoL construct.

The robust factor structure allows researchers to analyze both the overall quality of life score and specific subscale scores, providing detailed information about the areas most affected by the cancer experience. This factor structure has been replicated across various cultures and languages, supporting the generalizability of the FACT-G as a robust cross-cultural measure.

Instrument

Test Type: Self-report questionnaire / Patient Reported Outcome (PRO) measure.

Format: The instrument typically consists of 27 items (in the FACT-G core version) rated on a five-point Likert scale (0 to 4), usually anchored by ratings such as (0) Not at all, (1) A little bit, (2) Some- what a bit, (3) Quite a bit, and (4) Very much so. Items generally refer to the patient’s experience over the past 7 days.

Language Available: Extensive translations available globally. Validation studies confirm translations into Spanish, various African languages, and many others (Bonomi et al., 1996; Mullin et al., 2000; Cella et al., 1998).

Population Group: Clinical population; adult patients diagnosed with cancer of any type or stage.

Age Group: Adults.

Population Details: Used across heterogeneous oncology populations, including those receiving curative, adjuvant, or palliative treatments.

Test Methodology: Patients self-administer the instrument, circling the number that best reflects how true each statement has been for them during the preceding week. The total score is derived by summing the subscale scores, with specific items reverse-scored to ensure higher scores consistently reflect better QoL.

Keywords

HRQoL, Oncology Care, Patient Outcomes, FACT System, Measurement Scale, Psychometrics, Clinical Assessment, Health Status, Reliability, Validity.

Authors

Author ORCID Identifier: Not provided in source content.

Affiliation Email addresses: [email protected]

Correspondence Address: Not provided in source content.

Permissions & Fee and Test Year

The Functional Assessment of Cancer Therapy (FACT-G) was initially developed and validated in 1993 (Cella et al.). The scale is maintained and licensed by the FACIT Measurement System. While the instrument is frequently available free of charge for academic, non-commercial research purposes, formal permission is required for its use. Commercial or industry-sponsored use typically requires licensing and payment of associated fees. Users are advised to contact the FACIT organization directly to ascertain current licensing and permission requirements.

Reference’s

The instrument itself can be found in academic literature. The original validation paper is available in PDF format here: http://ascopubs.org/doi/pdf/10.1200/jco.1993.11.3.570. Another resource for the instrument is provided here: www.a4ebm.org/sites/default/files/Measuring%20Health.pdf.

• Bonomi, A.E., Cella, D.F., Hahn, E.A., et al. (1996). Multilingual translation of the Functional Assessment of Cancer Therapy (FACT) quality of life measurement system. Qual Life Res, 5:309–320.
• Brady, M.J., Cella, D.F., Mo, F., et al. (1997). Reliability and validity of the Functional Assessment of Cancer Therapy-Breast quality-of-life instrument. J Clin Oncol, 15:974–986.
• Cella, D.F. (1992). Quality of life: the concept. J Palliat Care, 8:8–13.
• Cella, David. (1993). “Quality of Life: Concepts and Definition”. Journal of Pain and Symptom Management. 9: 186–192.
• Cella, D.F., Tulsky, D.S., Gray, G., et al. (1993). The functional assessment of cancer therapy scale: development and validation of the general measure. Journal of Clinical Oncology, 11(3):570–579.
• Cella, D.F., Bonomi, A.E., Lloyd, S.R., et al. (1995). Reliability and validity of the Functional Assessment of Cancer Therapy-Lung (FACT-L) quality of life instrument. Lung Cancer, 12:199–220.
• Cella, D.F., Bonomi, A.E. The Functional Assessment of Cancer Therapy (FACT) and Functional Assessment of HIV Infection (FAHI) quality of life measurement system. In: Spilker B, ed. Quality of life and pharmacoeconomics in clinical trials. Philadelphia: Lippincott-Raven, 1996:203–214.
• Cella, D. (1997). The Functional Assessment of Cancer Therapy-Anemia (FACT-An) Scale: a new tool for the assessment of outcomes in cancer anemia and fatigue. Seminars in Hematology [1997, 34(3 Suppl 2):13-19].
• Cella, D., Hernandez, L., Bonomi, A.E., et al. (1998). Spanish language translation and initial validation of the Functional Assessment of Cancer Therapy quality-of-life instrument. Med Care, 36:1407–1418.
• Fairclough, D.L, Cella, D.F. (1996). Functional Assessment of Cancer Therapy (FACT-G): non-response to individual questions. Qual Life Res, 5:321–329.
• McDowell, Ian. (2006). Measuring Health: A Guide to Rating Scales and Questionnaires, Third Edition. OXFORD UNIVERSITY PRESS.
• Mullin, V., Cella, D., Chang, C-H., et al. (2000). Development of three African language translations of the FACT-G. Qual Life Res, 9:139–149.
• Novik, A.A., Ionova, T.I., Fedorenko, D.A., et al. (2000). Sensitivity of FACT-G in quality of life assessment of lung cancer patients after radical surgery. Quality of Life Newsletter, 24:12.
• Ward, W.L., Hahn, E.A., Mo, F., et al. (1999). Reliability and validity of the Functional Assessment of Cancer Therapy-Colorectal (FACT-C) quality of life instrument. Quality of Life Research, 8(3):181–195.

Items of the Functional Assessment of Cancer Therapy (FACT-G)

The scale items below reflect the content utilized in Versions 3 and 4 of the FACT-G, referencing the patient’s experience during the past 7 days. Responses are typically rated on a 5-point Likert scale (0 to 4).

Version 4 Items

During the past 7 days.

Physical Well-being

• I have a lack of energy
• I have nausea
• Because of my physical condition, I have trouble meeting the needs of my family
• I have pain
• I am bothered by side effects of treatment
• I feel ill
• I am forced to spend time in bed

Social/Family Well-being

• I feel close to my friends
• I get emotional support from my family
• I get support from my friends
• My family has accepted my illness
• I am satisfied with family communication about my illness
• I feel close to my partner (or the person who is my main support)
• Regardless of your current level of sexual activity, please answer the following question. If you prefer not to answer it, please check this box [ ] and go to the next section. I am satisfied with my sex life

Emotional Well-being

• I feel sad
• I am satisfied with how I am coping with my illness
• I am losing hope in the fight against my illness
• I feel nervous
• I worry about dying
• I worry that my condition will get worse

Functional Well-being

• I am able to work (include work at home)
• My work (include work at home) is fulfilling
• I am able to enjoy life
• I have accepted my illness
• I am sleeping well
• I am enjoying the things I usually do for fun
• I am content with the quality of my life right now

Version 3 Items and Additional Domains

During all the past 7 days:

PHYSICAL WELL-BEING

1. I have a lack of energy
2. I have nausea
3. I have trouble meeting the needs of my family
4. I have pain
5. I am bothered by side effects of treatment
6. In general, I feel sick
7. I am forced to spend time in bed
8. How much does your PHYSICAL WELL-BEING affect your quality of life? Not at all 0 1 2 3 4 5 6 7 8 9 10 Very much so

SOCIAL/FAMILY WELL-BEING

9. I feel distant from my friends
10. I get emotional support from my family
11. I get support from my friends and neighbors
12. My family has accepted my illness
13. Family communication about my illness is poor If you have a spouse/partner, or are sexually active, please answer #14-15. Otherwise, go to #16.
14. I feel close to my partner (or main support)
15. I am satisfied with my sex life
16. How much does your SOCIAL/FAMILY WELL-BEING affect your quality of life? Not at all 0 1 2 3 4 5 6 7 8 9 10 Very much so

RELATIONSHIP WITH DOCTOR

17. I have confidence in my doctor(s)
18. My doctor is available to answer my questions
19. How much does your RELATIONSHIP WITH THE DOCTOR affect your quality of life? Not at all 0 1 2 3 4 5 6 7 8 9 10 Very much so

EMOTIONAL WELL-BEING

20. I feel sad
21. I am proud of how I’m coping with my illness
22. I am losing hope in the fight against my illness
23. I feel nervous
24. I worry about dying
25. How much does your EMOTIONAL WELL-BEING affect your quality of life? Not at all 0 1 2 3 4 5 6 7 8 9 10 Very much so

FUNCTIONAL WELL-BEING

26. I am able to work (include work in home)
27. My work (include work in home) is fulfilling
28. I am able to enjoy life “in the moment”
29. I have accepted my illness
30. I am sleeping well
31. I am enjoying my usual leisure pursuits
32. I am content with the quality of my life right now
33. How much does your FUNCTIONAL WELL-BEING affect your quality of life? Not at all 0 1 2 3 4 5 6 7 8 9 10 Very much so