Quality of Life Assessment in Culturally Diverse Populations
Quality of Life Assessment in Culturally Diverse Populations
CHICAGOWhile the main objective in caring for cancer patients
has been to prolong life and to focus on short-term and long-term
survival, more recent efforts include considerations of
health-related quality of life (QOL).[1,2] The World Health
Organization defines QOL as not merely the absence of disease
but a state of physical, emotional, and social well being.
Evaluation of QOL involves assessments of a wide spectrum of human
functioning, including emotional response to cancer and treatment,
physical activity, and the impact of the specific cancer on physical
and psychological capacities. QOL now constitutes an important part
of study for epidemiology, clinical trials, and health services
From a cancer surveillance perspective, information about
health-related QOL is important because it provides indicators for
trends in cancer treatments and their impact on patients lives.
From a clinical trialists perspective, QOL outcomes are
increasingly included as endpoints in oncology clinical trials.
Finally, from the perspective of health services research, health-related
QOL is considered a major part of medical outcomes research, since a
cancer patients life is a highly dynamic experience.
Since many oncology treatments do not cure cancer but can extend life
for long periods of time, it is wise to examine all aspects of
disease burden to allow accurate assessment of therapeutic progress.
Although many clinical trials, outcomes studies, and epidemiology
studies now include health-related QOL assessments for persons with
many different types of cancer, efforts that include large numbers of
racial/ethnic minorities are rare.
Most of the questionnaires used to assess QOL in clinical settings
are written in English and are tailored for relatively highly
educated, white populations. The content and format of the
questionnaires can act as a barrier that immediately precludes
numerous cancer patients from socioeconomically and ethnically
diverse populations, or whose first language is not English.
In recent years, this problematic situation has gained attention and
motivated researchers to begin drafting instruments that allow for
accurate evaluation of populations that speak languages other than
English and who have different daily life circumstances.
In addition, QOL measurement in cancer patients can present further
challenges when the disease has markedly affected physical, role,
social, and emotional functioning, making adherence to
self-administered questionnaires difficult.
In this article, we focus on the work of three researchers who
presented papers at the 1999 Robert H. Lurie Comprehensive Cancer
Center Health Policy Symposium: Frank Baker, MD, of the American
Cancer Society; David Cella, PhD, of the Evanston/Northwestern
Healthcare System and Northwestern University; and Sara J. Knight,
PhD, of the VA Chicago Healthcare System/Lakeside Division and
All three have been actively involved in developing appropriate
methods for evaluating the QOL of patients with cancer in culturally
Dr. Frank Bakers research is based on the practical observation
that QOL measurement in cancer patients from lower socioeconomic and
minority backgrounds presents numerous chal-lenges. His work has
focused on delivering information regarding the cultural equivalence
of QOL instruments so that they may be used across culturally diverse
In one study he described, only a minority of the different QOL
measures demonstrated adequate reliability and validity for black and
Hispanic populations. It was further shown that the family
functioning dimension was particularly difficult to address across
the different cultural backgrounds, because of widely variant
attitudes toward this domain.
Dr. Bakers research is novel, since most QOL instruments
include predominantly middle-class white cohorts and since normative
QOL data on specific populations, categorized by socioeconomic
status, cultural identity, and literacy level, generally are not available.
In response to this issue, the appropriateness of several existing
QOL instruments has been evaluated and new methods developed for
assessing QOL in minority populations.
Dr. Baker and his colleagues have identified five main areas of QOL
testing that make up the core elements required to evaluate a
persons physical and psychological health state.
The first is cultural equivalence, which refers to whether the items
in the questionnaires are relevant to the specific lifestyle
background of the population.
Another important aspect of determining instrument validity is
semantic equivalence, referring to the way questions are worded.
Questions should be presented in Spanish to a Spanish-speaking group
of patients. It is also critical that the phrases be written in the
everyday language of the cohort, because people may use different
dialects and have different Spanish literacy levels.
Technical equivalence determines whether the different QOL
instruments are actually measuring the same aspects of health.
Finally, criteria equivalence and conceptual equivalence, as
ascertained by statistical method analyses, ensure that the same
ideas are being examined across cultures.
Dr. Bakers research includes analyses of various aspects of QOL
testing for several instruments that are administered to patients
with various types of cancer. To achieve cultural equivalence among
the various QOL surveys and eliminate potential interviewer bias, Dr.
Baker suggests that the operational aspects of the research
incorporate several safety guidelines.
Interviewers are trained nurses, usually from a similar background as
the patient. This may allow the patient to feel slightly more
comfortable in the interview setting and to give more candid
The interviews are structured so that they are easy to understand and
are administered face-to-face rather than over the telephone, to
further reduce discomfort of the participants.
In addition, the interviewers evaluate the entire process and provide
essential feedback to help improve the patient/interviewer interaction.
Developing Better QOL Measures
Dr. David Cellas research is dedicated to developing better,
more relevant, and more culturally appropriate QOL measures,[6,7]
including the Functional Assessment of Cancer Therapy-General Scale
(FACT-G) (the fourth version is currently used), a 27-item
questionnaire written at the third-grade level.
Dr. Cella and his colleagues have shown that there are no significant
differences in the validity of the FACT-G between high-literacy and
low-literacy populations or between interview-assisted or
self-administration assessment methods.
In another 3-year National Cancer Institute funded study, the
Bilingual Intercultural QOL project, Dr. Cellas team translated
the English FACT into Spanish and tested its reliability. Translation
from one language to another, however, does not always guarantee that
meaning is preserved. As a result, QOL assessments for cohorts made
up of Hispanics using the Spanish version of a test cannot be
compared with those obtained from cohorts of whites.
Furthermore, Dr. Cella has pointed out that the conception of QOL is
embedded within any given culture, and, therefore, it is impossible
to expect any measure of QOL to be void of cultural influence.
Nonetheless, the research indicates that we can expect a good QOL
instrument to be culture equivalent.
Dr. Cellas presentation stemmed from his previous work on these
issues and focused on cultural differences that affect the validity
of QOL questionnaires as well as the low-literacy issues surrounding
quality of health care.