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Quality-of-Life Outcomes in the Evaluation of Head and Neck Cancer Treatments
Seth Schwartz, MD;
Donald L. Patrick, PhD, MSPH;
Bevan Yueh, MD
Arch Otolaryngol Head Neck Surg. 2001;127:673-678.
ABSTRACT
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Objectives To review the published literature to evaluate the design, use of terminology,
and interpretation of results in studies using quality-of-life (QOL) instruments
to measure differences between head and neck cancer treatments at a point
in time or to report changes over time in one or more treatment groups.
Data Source MEDLINE search for subject headings "head and neck neoplasms" (as a
main topic) and "quality of life" or "health status" restricted to English-language
sources and a 10-year period from 1989 to 1999.
Study Selection Four hundred forty-five abstracts were reviewed to find articles using
an instrument to compare head and neck cancer therapy groups with a QOL outcome
(13.7% included).
Data Extraction Two readers reviewed each article to determine how terminology was used,
if a scientific study design was used, and if differences or changes in scores
were clinically interpreted.
Results Sixty-one articles were reviewed. Forty different instruments were used.
Terminology was used inconsistently in 21 (34.4%) of the 61 articles. A scientific
study design was used in only 11 (18.0%) of the 61 articles (P<.001). A clinical interpretation of results was given in 16 (26.2%)
of the 61 articles (P<.001).
Conclusions While QOL outcomes show promise for assisting with treatment decisions
in head and neck cancer therapy, few studies using instruments to measure
QOL outcomes are hypothesis driven and clinical interpretations of results
are not commonly provided. We recommend that future studies identify the construct
to be measured, specify comparator groups and hypotheses a priori, and provide
clinical interpretations of results.
INTRODUCTION
HEAD AND NECK cancer represents about 5% of cancers diagnosed annually.
Head and neck cancer generally refers to squamous cell carcinoma of the nasopharynx,
oral cavity, oropharynx, hypopharynx, or larynx. Surgery and radiotherapy
are the 2 primary modes of therapy for head and neck cancer, although chemotherapy
is increasingly used for advanced disease. Despite intensive work in developing
new treatment alternatives, these treatments have, thus far, had little influence
on survival in most subsites of the head and neck.1, 2
Since the consequences of cancer therapy for the patient can be debilitating
and may depend on the modality of treatment, increasing attention has been
given to other measures of outcome such as functional status and quality of
life (QOL).
Evidence of the importance of these outcomes for evaluating treatment
effectiveness is seen in the proliferation of instruments for quantifying
QOL. Since 1989, there have been more than 300 articles in the head and neck
literature that refer specifically to QOL. However, there is wide variation
in what is meant by "quality of life." Authors have used QOL to refer to a
variety of distinct concepts, such as symptoms alone, functional status, health
status, health-related quality of life (HrQOL), and overall (global) QOL.
Global QOL encompasses a patient's social; emotional; psychological; and physical
functional status, symptoms such as pain; and environmental factors such as
income, opportunities, family support, and lifestyle choices. These individual
components are referred to as "domains." Because factors such as income and
family support are often unaffected by treatment, clinicians generally focus
on HrQOL,3 which refers to the aspects of QOL
pertaining to a health or medical concern.
For broad discussions about QOL, the failure to draw distinctions between
the various domains of QOL is usually not problematic. However, precise scientific
study of these issues rely on psychometric questionnaires (instruments) that
target a specific construct such as HrQOL or functional status. When authors
do not specify what construct they are measuring, the meaning of the results
can be ambiguous and the appropriateness of the chosen instrument can be difficult
to determine. In this article, we will use the term QOL to refer to all QOL–related
constructs that were obtained through the use of questionnaires, and use the
term HrQOL to distinguish it from other domains such as functional status.
Most instruments report outcomes as numerical scores. Studies use these
scores to compare 2 or more treatment groups at a point in time (discriminative)
or 1 or more groups receiving the same treatment over time (evaluative). Instruments
may prove sensitive to differences in QOL scores between groups or changes
over time, but interpreting what a given change score or difference in scores
means is still a difficult task.4, 5
In other words, finding a statistically significant difference between treatment
groups does not guarantee that the difference is clinically relevant. Specifically,
reported results may not be meaningful to clinicians or patients hoping to
gain guidance from published studies. Standards for reporting results in an
interpretable manner are evolving rapidly.3, 6
Several studies exist that evaluate the validity and method of QOL measurement
in the general medical literature, but, to our knowledge, no studies have
investigated how well instruments are being used to measure QOL outcomes in
head and neck cancer.7, 8 This
study evaluated how discriminative and evaluative differences are studied
and reported in the head and neck literature and evaluated whether these differences
have been clinically interpreted. To do this we reviewed all discriminative
and evaluative studies on QOL in head and neck cancer identified through MEDLINE.
We hypothesized that there would be many studies that were inaccurate in their
use of terminology describing QOL outcomes, failed to use hypothesis-driven
study designs, and failed to interpret the clinical significance of reported
differences.
MATERIALS AND METHODS
SEARCH STRATEGY
A MEDLINE search was performed through the National Library of Medicine's
Internet site "Internet Grateful Med." Search terms were "head and neck neoplasm"
as a main topic and "quality of life" or "health status." The search was then
limited to the English-language sources and to a 10-year period from 1989
to 1999. This search strategy resulted in 445 articles.
Part 1: Exclusion and Classification of Articles
The 445 abstracts were then reviewed and classified by content and study
design to identify those addressing QOL and antineoplastic treatments (including
reconstruction) for squamous cell carcinoma of the nasopharynx, oral cavity,
oropharynx, hypopharynx, or larynx. One of us (S.S.) reviewed all abstracts
to identify articles that met inclusion criteria, and the 2 additional investigators
(D.L.P. and B.Y.) each reviewed the same 10% of the articles chosen at random
to assess correlation ( = 0.89, P<.001).
Articles about the esophagus (n = 113), the thyroid gland (n = 17), or other
topics not specifically head and neck cancer (n = 19, Table 1) were excluded. Twelve articles were excluded because they
reported on interventions that were not cancer treatments (ie, nutritional
interventions, psychosocial interventions, screening, or smoking cessation
interventions). Twenty-one articles that studied only nutritional status,
not QOL, were excluded. Sixty-one articles reported studies in which QOL was
not assessed (an article was classified as assessing QOL if either it expressed
intent to assess QOL or it reported the effect of a treatment on QOL in the
abstract). Eighty-two articles did not report primary data (these included
letters, reviews, and didactic articles). Fourteen articles were excluded
because they presented or validated a new instrument or measuring technique
but did not report primary data. Two articles were excluded because they compared
2 or more instruments but not different patient groups. Five studies were
excluded because they compared QOL ratings made by patients with those made
by caregivers about the patient. One article was a nonhuman study.
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Table 1. Reasons for Exclusions of Articles*
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The remaining 98 articles were then classified based on whether an instrument
was used and whether discriminative or evaluative comparisons were made. Sixty-one
papers used an instrument to make comparisons. These articles were the subjects
of the second part of the study.9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68
Part 2: Evaluating Study Design, Reporting of Differences, and Interpretability
In part 2 of the study, the 61 articles that used an instrument to make
comparisons between groups or over time were reviewed to answer 3 study questions.
Was the QOL Domain of Interest Appropriately Identified and Measured?
We examined whether authors defined the construct they intended to measure
and used terminology accurately. Accuracy primarily required making distinctions
between general QOL and the specific construct or domain that was measured
(HrQOL, physical functioning, emotional functioning, or another domain). In
articles in which several terms were used, the accuracy of usage for each
term was evaluated. Second, we examined whether chosen instruments actually
measured what the authors wanted to measure. Finally, wequeried whether the
instrument used was psychometrically validated. To be considered valid, we
required that the article at least referenced the study in which the psychometric
properties of the chosen instrument were described.
Was a Scientific Study Design Used?
We asked if comparator groups were specified a priori and a formal hypothesis
was tested. All clinical studies should have an explicit hypothesis to test
because this increases the clinical plausibility and decreases the possibility
that observed differences resulted by chance.69
For this review, the investigators had to state explicitly which group they
expected to have a better outcome and present this hypothesis in the "Introduction"
or "Methods" section of the article to be credited. To be considered a priori,
the comparator groups had to be explicitly defined and the comparison between
them considered a goal of the study. Post hoc comparisons or partitioning
of the data were not credited.
Was an Effort Made to Interpret Differences in QOL Scores?
This consideration primarily applied to articles that used instruments
with composite scores or composite domain scores. Composite scores are obtained
by combining the results of multiple questions into a single score. Composite
scores can be difficult to interpret because they do not reflect an answer
to any one question. To determine if investigators interpreted score differences
or changes in scores over time, we used criteria established by the Scientific
Advisory Committee (SAC) of the Medical Outcomes Trust.70
Scientific Advisory Committee of the Medical Outcomes Trust recently compiled
recommendations for the clinical interpretation of QOL data.70
They advocated 2 principal methods. The first is through use of an explicitly
stated minimally important difference. This means that the investigation must
state a priori how big a difference there must be between groups to be clinically
meaningful. The second is by using familiar clinical anchors. This means that
QOL scores are related to clinically familiar concepts like community norms,
recognized clinical conditions, recognized life events, or meaningful adjectives
like "better" and "worse." We used these guidelines to perform this review.3, 4, 6
While a discussion of the importance of interpretability has been present
in the health outcomes literature for years, these guidelines were not published
at the time several of the earlier articles were published. Therefore, we
were generous in giving credit for fulfilling these guidelines. Any attempt
to use these criteria was credited as achieving interpretability. In addition,
credit was given if 2 readers (D.L.P. and B.Y.) concurred that the results
were clinically interpretable. For example, a single-item instrument with
adjectives like "worse," "same," and "better" as potential answers was usually
interpretable.
DATA COLLECTION AND ANALYSIS
A form was developed to standardize data extraction from the articles.
Ten percent of the 61 articles were selected at random to test the extraction
questionnaire. Each of the 3 reviewers read and extracted data from the selected
articles. The judgments of each reviewer were then compared and discussed.
Minor corrections to the data extraction form were made to ensure clarity
and accuracy of data extraction. All 61 articles were then reviewed again.
One investigator read all of the articles (S.S.) while the other 2 investigators
(D.L.P. and B.Y.) split the articles. Each article was, therefore, reviewed
by 2 investigators. Data extraction results were then compared for each article.
Disputes were resolved by consensus. Data were analyzed using a test of binomial
proportions in Statistical Product and Service Solutions (SPSS Inc, Chicago,
Ill), a statistical software package.
RESULTS
A total of 98 articles were grouped and classified. Thirty-three articles
(33.7%) were descriptive studies in which a case or case series was presented
or a description of a single group of patients was presented leaving 65 studies
(66.3%) that made comparisons. Sixty-one (93.8%) of the 65 comparative studies
used an instrument. These 61 articles were the subject of part 2 of this study.
We then classified the types of comparisons made in each of the 61 articles.
Several studies contained more than one form of comparison. Twenty-eight articles
(45.9%) compared 2 or more groups receiving different cancer therapies. Nineteen
(31.1%) of the remaining articles compared scores at 2 or more distinct points
in time (ie, before and after treatment), but did not separate groups by type
of cancer treatment. The remaining 14 studies (23.0%) compared scores in 2
or more groups defined by patient, demographic, or disease characteristics,
but not by treatment type or over time.
Overall, 40 different instruments were used. Of these, 30 were previously
validated. The EORTC QLQC-30 (European Organization for Research and Treatment
of Cancer Quality of Life Questionnaire 30) was the most commonly used instrument
(n = 15). The head and neck module of the EORTC was used in 13 articles. The
University of Washington Quality of Life questionnaire was the next most commonly
used instrument (n = 9). In 10 articles (16.4%), at least one instrument was
used inappropriately. In most circumstances, this means that an instrument
designed to measure functional status or performance status was erroneously
used to measure overall QOL.
Throughout the articles, 16 different terms were used to classify QOL
outcomes. The general term "quality of life" was the most commonly used term.
It was used in 38 articles (62.3%). Functional status and HrQOL were the next
most common terms. They were used in 16 (26.2%) and 7 (11.5%) of the articles,
respectively. Other commonly used terms included "health status," "life satisfaction,"
"well-being," "utility," "performance status," and "psychological function."
Inaccurate usage of terminology was also most common with QOL. In 17
(44.7%) of 38 articles, the usage was inaccurate. Inaccuracies usually resulted
from failing to recognize distinctions between functional status and overall
QOL. The terms health status and well-being were used synonymously with quality
of life. The same inaccuracies occurred with these terms. The other term not
used appropriately was performance status, which was also equated to QOL in
one article. Overall, 21 (34.4%) of the articles used at least 1 term inaccurately.
Few articles used a proper scientific study design. Fifty-two articles
(85.2%, P<.001) specified comparator groups a
priori. Only 11 (18%) of the 61 articles (P<.001)
stated a testable hypothesis.
Only 16 articles (26.2%) had some form of clinical interpretation of
results (P<.001, Table 2). Six articles addressed neither the statistical nor the
clinical implication of their findings. Clinical significance was most commonly
established using interpretive anchors such as community norms or classifying
adjectives like better, worse, and same (14 of 16 articles). Three of the
articles specified what a minimally importance difference in scores was. For
example, several of the articles using the 36-Item Short-Form Health Survey
specified that a 10-point difference in score was clinically significant.
There were no other notable methods used for interpreting between group mean
score differences. Prior to 1993 there were no articles with an attempt at
interpretation. After 1993, more articles were identified per year and more
made efforts at interpretation. The proportion of articles with interpretation,
however, did not increase significantly from 1994 to 1999.
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Table 2. Percentage of the 61 Studies Using Method for Establishing
Significance
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COMMENT
The goal of QOL measurement in this field is primarily to make informed
decisions between treatment alternatives. Reliably measuring QOL outcomes
and reporting differences in a clinically meaningful way is critical. Studies
that use a validated instrument to measure QOL scores for a treatment group,
compare those results to QOL scores for another treatment group, and report
the difference in a meaningful fashion have the potential to aid clinicians
and patients who are trying to decide between competing treatment strategies.
It is in this context that this review of the head and neck literature
was undertaken. Sixty-one (93.8%) of the articles that intended to measure
discriminative or evaluative differences used an instrument. While there are
no data to compare the performance of the head and neck literature with that
of other medical specialties, 93.8% represents widespread recognition of the
need to explicitly measure QOL.
In total, 40 different instruments were used in the 61 articles that
we reviewed. Ten unvalidated instruments were used and 10 were inappropriately
used. This means that these articles reported different outcomes than were
actually measured or they reported outcomes that may not have been measured
accurately.
Basic to the idea of interpretability is the concept of familiarity.
Once clinicians become familiar with a measure through repeated applications,
the measure tends to become more meaningful. A frequently used example to
explain this concept is the measurement of blood pressure. High blood pressure
is defined as a systolic pressure of 140 mm Hg or greater. There is nothing
inherently meaningful about the number 140 mm Hg, but this cutoff point has
meaning because it is so commonly used. Ideally, QOL measurement would achieve
similar familiarity. With so many different instruments in use, many of which
purport to measure the same things, it is nearly impossible for practitioners
to become familiar with scoring norms and clinically meaningful cutoff points
in all of the instruments. Narrowing the number of instruments in use would
enhance the meaning of results from QOL outcome studies, but this is impracticable
as no instrument has come to represent a standard criterion and different
instruments measure different domains.
There is no reliable or acceptable way to determine how independent
domains should be combined to provide an overall QOL score. The complexity
of these relationships lends to the confusion surrounding what is meant by
QOL. Therefore, it is important to use terminology accurately. We found 16
different terms used to label QOL outcomes. Quality of life was the most common.
It was also the term most frequently used inaccurately or inappropriately.
With one exception, the other terms used inaccurately also involved failure
to distinguish specific domains from general catchall phrases.
A principal component of scientific evaluation is hypothesis testing.
Only 11 studies (18.0%) stated an explicit hypothesis. These results support
our own hypothesis that many QOL studies are not hypothesis driven. Some investigators
expressed intent to compare groups or evaluate treatments, but they did not
state which group they expected to have a superior outcome. Some even commented
that their results either met with or contradicted their expectation, but
they did not state these expectations in their introduction or experimental
design. These articles were not credited here as having a hypothesis. Comparative
studies using QOL measures as a basis for comparison are both more valid and
easier to understand if an explicitly stated hypothesis is tested.
Another scientific issue was potentially biased conclusions from missing
data. For example, patients with recurrent disease were excluded from evaluation
in 19 (35.2%) of 54 articles to which this applies (the time frame of some
of the studies was too short for disease to recur). These patients are likely
doing worse than those without recurrence. Excluding them from an analysis
results in artificially improved QOL scores. If disease recurred in equal
percentages of each comparator group, this may not bias the comparison, but
routine exclusion of patients with ongoing disease from QOL assessment misrepresents
the actual burden of QOL lost or gained.
All of the studies included in this review compared the QOL scores of
multiple, distinct groups or of one group over time. In each instance, mean
scores were reported and the authors drew a conclusion about which group had
better HrQOL (or was superior in some independent domain) based on these scores.
According to the guidelines explained above, only 16 investigators (26.2%)
made some effort to interpret the clinical meaning of the difference that
was measured. These results support our second hypothesis that many current
QOL studies do not make an attempt to interpret results. While articles stressing
the importance of clinical interpretability have been published in the literature
for over 10 years, it is only in the last few years that more general acceptance
of these concepts became widespread. Consequently, we compared the use of
interpretation by year of publication. While none of the articles published
prior to 1993 interpreted results, 5 (38.5%) of 13 articles published in 1999
used some method to interpret the clinical meaning of the results. In recent
years, however, the percentage of articles with interpretation has not increased
markedly. In this review, our bias was toward giving credit for interpretation
if any effort was made to do so. Strictly speaking, several of the articles
to which we gave credit fall short of actually meeting full criteria for interpretability.
Future investigators may consider correlating QOL outcomes to currently meaningful
anchors like performance status indices, time to recurrence, or weight loss.
There are major obstacles to performing research on QOL outcomes in
general. These can be divided into 2 major categories: practical and methodological.
Practical considerations include the amount of time and resources required
to collect and analyze large amounts of questionnaire data, the difficulty
in selecting an appropriate instrument, and, as mentioned above, the bias
created by missing data on those most severely affected by their disease.
Methodological considerations include the inability of instruments to capture
patient's adaptation to the conditions of their disease state, the difficulties
of comparing outcomes across populations, and, as we emphasize in this article,
the lack of interpretation of what QOL score differences mean in clinical
practice.
Despite these barriers, the importance of using QOL outcomes in evaluating
head and neck cancer treatment has grown because it shows promise as a means
of deciding between treatments when no survival advantage is afforded by one
modality over another. However, if the results of QOL studies are not made
meaningful to clinicians, the potential of these measures will not be realized.
Therefore, we make the following recommendations. Studies using instruments
to measure QOL outcomes and to compare groups should be precise in their identification
of what construct is to be measured, for example, HrQOL, functional status,
or depression. Comparator groups should be identified a priori and a testable
hypothesis should be presented. Finally, the clinical importance of reported
differences must be interpreted using familiar anchors or minimally important
differences until the instruments are more widely used and their scores understood.
AUTHOR INFORMATION
Accepted for publication Janaury 18, 2001.
This investigation was supported in part by Basic Sciences Training
in Otolaryngology grant DC00018 from the National Institutes of Health, Bethesda,
Md (Dr Schwartz), and by career development award CD-98318 from the Department
of Veterans Affairs, Veterans Health Administration, Health Services Research
and Development Service, Washington, DC (Dr Yueh).
The views expressed in this article are those of the authors and do
not necessarily represent the views of the Department of Veterans Affairs.
From the Department of Otolaryngology–Head and Neck Surgery,
University of Washington School of Medicine (Drs Schwartz and Yueh), and the
Departments of Health Services and Epidemiology, University of Washington
(Dr Patrick), and the Health Service Research and Development Service, Veterans
Affairs Puget Sound Health Care System (Dr Yueh), Seattle, Wash.
Corresponding author and reprint: Seth Schwartz, MD, Otolaryngology–Head
and Neck Surgery, University of Washington Medical Center, 1959 NE Pacific
St, Box 356515, Seattle, WA 98195-6515 (e-mail: schwarsr{at}u.washington.edu).
REFERENCES
| |
1. The Department of Veterans Affairs Laryngeal Cancer Study Group. Induction chemotherapy plus radiation compared with surgery plus radiation
in patients with advanced laryngeal cancer. N Engl J Med. 1991;324:1685-1690.
ABSTRACT
2. Lefebvre J, Chevalier D, Luboinski B, Kirkpatrick A, Collette L, Sahmoud T for the EORTC Head and Neck Cancer Cooperative. Larynx preservation in pyriform sinus cancer: preliminary results of
a European Organization for Research and Treatment of Cancer phase III trial. J Natl Cancer Inst. 1996;88:890-899.
FREE FULL TEXT
3. Guyatt GH, Feeny DH, Patrick DL. Measuring health-related quality of life. Ann Intern Med. 1993;118:622-629.
FREE FULL TEXT
4. Deyo RA, Patrick DL. The significance of treatment effects: the clinical perspective. Med Care. 1995;33(suppl 4):AS286-AS291.
5. Yueh B, Feinstein A. Abstruse comparisons: the problem of numerical contrasts of two groups. J Clin Epidemiol. 1999;52:13-18.
FULL TEXT
|
ISI
| PUBMED
6. Lydick EG, Epstein RS. Clinical significance of quality of life data. In: Spilker B, ed. Quality of Life and Pharmacoeconomics
in Clinical Trials. 2nd ed. Philadelphia, Pa: Lippincott-Raven; 1996:461-465.
7. Lara-Munoz C, Feinstein A. How should quality of life be measured? J Investig Med. 1999;47:17-24.
ISI
| PUBMED
8. Gill T, Feinstein A. A critical appraisal of the quality of quality-of-life measurements. JAMA. 1994;272:619-626.
FREE FULL TEXT
9. Robert F, Soong SJ, Wheeler RH. A phase II study of topotecan in patients with recurrent head and neck
cancer: identification of an active new agent. Am J Clin Oncol. 1997;20:298-302.
FULL TEXT
|
ISI
| PUBMED
10. Zelefsky MJ, Gaynor J, Kraus D, Strong EW, Shah JP, Harrison LB. Long-term subjective functional outcome of surgery plus postoperative
radiotherapy for advanced stage oral cavity and oropharyngeal carcinoma. Am J Surg. 1996;171:258-261; discussion 262.
FULL TEXT
|
ISI
| PUBMED
11. DeSanto LW, Olsen KD, Perry WC, Rohe DE, Keith RL. Quality of life after surgical treatment of cancer of the larynx. Ann Otol Rhinol Laryngol. 1995;104:763-769.
ISI
| PUBMED
12. Stewart MG, Chen AY, Stach CB. Outcomes analysis of voice and quality of life in patients with laryngeal
cancer. Arch Otolaryngol Head Neck Surg. 1998;124:143-148.
FREE FULL TEXT
13. Hammerlid E, Ahlner-Elmqvist M, Bjordal K, et al. A prospective multicentre study in Sweden and Norway of mental distress
and psychiatric morbidity in head and neck cancer patients. Br J Cancer. 1999;80:766-774.
FULL TEXT
|
ISI
| PUBMED
14. Terrell JE, Fisher SG, Wolf GT for the Veterans Affairs Laryngeal Cancer Study Group. Long-term quality of life after treatment of laryngeal cancer. Arch Otolaryngol Head Neck Surg. 1998;124:964-971.
FREE FULL TEXT
15. Bjordal K, Kaasa S. Psychological distress in head and neck cancer patients 7-11 years
after curative treatment. Br J Cancer. 1995;71:592-597.
ISI
| PUBMED
16. Mathieson CM, Logan-Smith LL, Phillips J, MacPhee M, Attia EL. Caring for head and neck oncology patients: does social support lead
to better quality of life? Can Fam Physician. 1996;42:1712-1720.
ISI
| PUBMED
17. Baker CA. Factors associated with rehabilitation in head and neck cancer. Cancer Nurs. 1992;15:395-400.
ISI
| PUBMED
18. Langius A, Bjorvell H, Lind MG. Oral- and pharyngeal-cancer patients' perceived symptoms and health. Cancer Nurs. 1993;16:214-221.
ISI
| PUBMED
19. Ma LC. Psychosocial stresses and adjustment of nasopharyngeal carcinoma patients
in Hong Kong: a panel study. Cancer Pract. 1996;4:258-266.
PUBMED
20. Rathmell AJ, Ash DV, Howes M, Nicholls J. Assessing quality of life in patients treated for advanced head and
neck cancer. Clin Oncol (R Coll Radiol). 1991;3:10-16.
21. Morton RP. Life-satisfaction in patients with head and neck cancer. Clin Otolaryngol. 1995;20:499-503.
ISI
| PUBMED
22. Bjordal K, Mastekaasa A, Kaasa S. Self-reported satisfaction with life and physical health in long-term
cancer survivors and a matched control group. Eur J Cancer B Oral Oncol. 1995;31B:340-345.
23. Langius A, Bjorvell H, Lind MG. Functional status and coping in patients with oral and pharyngeal cancer
before and after surgery. Head Neck. 1994;16:559-568.
ISI
| PUBMED
24. List MA, Ritter-Sterr CA, Baker TM, et al. Longitudinal assessment of quality of life in laryngeal cancer patients. Head Neck. 1996;18:1-10.
FULL TEXT
|
ISI
| PUBMED
25. McDonough EM, Varvares MA, Dunphy FR, Dunleavy T, Dunphy CH, Boyd JH. Changes in quality-of-life scores in a population of patients treated
for squamous cell carcinoma of the head and neck. Head Neck. 1996;18:487-493.
FULL TEXT
|
ISI
| PUBMED
26. Deleyiannis FW, Weymuller EA, Coltrera MD. Quality of life of disease-free survivors of advanced (stage III or
IV) oropharyngeal cancer. Head Neck. 1997;19:466-473.
FULL TEXT
|
ISI
| PUBMED
27. Funk GF, Karnell LH, Dawson CJ, et al. Baseline and post-treatment assessment of the general health status
of head and neck cancer patients compared with United States population norms. Head Neck. 1997;19:675-683.
FULL TEXT
|
ISI
| PUBMED
28. Morton RP. Laryngeal cancer: quality-of-life and cost-effectiveness. Head Neck. 1997;19:243-250.
FULL TEXT
|
ISI
| PUBMED
29. Hammerlid E, Wirblad B, Sandin C, et al. Malnutrition and food intake in relation to quality of life in head
and neck cancer patients. Head Neck. 1998;20:540-548.
FULL TEXT
|
ISI
| PUBMED
30. Murry T, Madasu R, Martin A, Robbins KT. Acute and chronic changes in swallowing and quality of life following
intraarterial chemoradiation for organ preservation in patients with advanced
head and neck cancer. Head Neck. 1998;20:31-37.
FULL TEXT
|
ISI
| PUBMED
31. Chaplin JM, Morton RP. A prospective, longitudinal study of pain in head and neck cancer patients. Head Neck. 1999;21:531-537.
FULL TEXT
|
ISI
| PUBMED
32. de Graeff A, de Leeuw RJ, Ros WJ, et al. A prospective study on quality of life of laryngeal cancer patients
treated with radiotherapy. Head Neck. 1999;21:291-296.
FULL TEXT
|
ISI
| PUBMED
33. Deleyiannis FW, Weymuller EA, Coltrera MD, Futran N. Quality of life after laryngectomy: are functional disabilities important? Head Neck. 1999;21:319-324.
FULL TEXT
|
ISI
| PUBMED
34. Rogers SN, Lowe D, Brown JS, Vaughan ED. The University of Washington head and neck cancer measure as a predictor
of outcome following primary surgery for oral cancer. Head Neck. 1999;21:394-401.
FULL TEXT
|
ISI
| PUBMED
35. Bundgaard T, Tandrup O, Elbrond O. A functional evaluation of patients treated for oral cancer: a prospective
study. Int J Oral Maxillofac Surg. 1993;22:28-34.
FULL TEXT
|
ISI
| PUBMED
36. Schliephake H, Schmelzeisen R, Schonweiler R, Schneller T, Altenbernd C. Speech, deglutition and life quality after intraoral tumour resection:
a prospective study. Int J Oral Maxillofac Surg. 1998;27:99-105. [published erratum appears in Int J
Oral Maxillofac Surg. 1998 Aug;27(4):322].
ISI
| PUBMED
37. Bjordal K, Kaasa S, Mastekaasa A. Quality of life in patients treated for head and neck cancer: a follow
up study 7 to 11 years after radiotherapy. Int J Radiat Oncol Biol Phys. 1994;28:847-856.
ISI
| PUBMED
38. Harrison LB, Zelefsky MJ, Armstrong JG, Carper E, Gaynor JJ, Sessions RB. Performance status after treatment for squamous cell cancer of the
base of tongue: a comparison of primary radiation therapy versus primary surgery. Int J Radiat Oncol Biol Phys. 1994;30:953-957.
ISI
| PUBMED
39. Moore GJ, Parsons JT, Mendenhall WM. Quality of life outcomes after primary radiotherapy for squamous cell
carcinoma of the base of tongue. Int J Radiat Oncol Biol Phys. 1996;36:351-354.
ISI
| PUBMED
40. Huguenin PU, Taussky D, Moe K, et al. Quality of life in patients cured from a carcinoma of the head and
neck by radiotherapy: the importance of the target volume. Int J Radiat Oncol Biol Phys. 1999;45:47-52.
FULL TEXT
|
ISI
| PUBMED
41. Kreitler S, Chaitchik S, Rapoport Y, Algor R. Psychosocial effects of level of information and severity of disease
on head-and-neck cancer patients. J Cancer Educ. 1995;10:144-154.
PUBMED
42. van der Donk J, Levendag PC, Kuijpers AJ, et al. Patient participation in clinical decision-making for treatment of
T3 laryngeal cancer: a comparison of state and process utilities. J Clin Oncol. 1995;13:2369-2378.
FREE FULL TEXT
43. List MA, Mumby P, Haraf D, et al. Performance and quality of life outcome in patients completing concomitant
chemoradiotherapy protocols for head and neck cancer. Qual Life Res. 1997;6:274-284.
ISI
| PUBMED
44. Schliephake H, Neukam FW, Schmelzeisen R, Varoga B, Schneller H. Long-term quality of life after ablative intraoral tumour surgery. J Craniomaxillofac Surg. 1995;23:243-249.
PUBMED
45. Konstantinovic VS. Quality of life after surgical excision followed by radiotherapy for
cancer of the tongue and floor of the mouth: evaluation of 78 patients. J Craniomaxillofac Surg. 1999;27:192-197.
PUBMED
46. Rogers SN, Hannah L, Lowe D, Magennis P. Quality of life 5-10 years after primary surgery for oral and oro-pharyngeal
cancer. J Craniomaxillofac Surg. 1999;27:187-191.
PUBMED
47. Jones E, Lund VJ, Howard DJ, Greenberg MP, McCarthy M. Quality of life of patients treated surgically for head and neck cancer. J Laryngol Otol. 1992;106:238-242.
ISI
| PUBMED
48. Schliephake H, Ruffert K, Schneller T. Prospective study of the quality of life of cancer patients after intraoral
tumor surgery. J Oral Maxillofac Surg. 1996;54:664-669; discussion 669-670.
FULL TEXT
|
ISI
| PUBMED
49. Mah SM, Durham JS, Anderson DW, et al. Functional results in oral cavity reconstruction using reinnervated
versus nonreinnervated free fasciocutaneous grafts. J Otolaryngol. 1996;25:75-81.
ISI
| PUBMED
50. Long SA, D'Antonio LL, Robinson EB, Zimmerman G, Petti G, Chonkich G. Factors related to quality of life and functional status in 50 patients
with head and neck cancer. Laryngoscope. 1996;106:1084-1088.
FULL TEXT
|
ISI
| PUBMED
51. Finizia C, Hammerlid E, Westin T, Lindstrom J. Quality of life and voice in patients with laryngeal carcinoma: a posttreatment
comparison of laryngectomy (salvage surgery) versus radiotherapy. Laryngoscope. 1998;108:1566-1573.
FULL TEXT
|
ISI
| PUBMED
52. Hammerlid E, Mercke C, Sullivan M, Westin T. A prospective quality of life study of patients with laryngeal carcinoma
by tumor stage and different radiation therapy schedules. Laryngoscope. 1998;108:747-759.
FULL TEXT
|
ISI
| PUBMED
53. Wilson KM, Rizk NM, Armstrong SL, Gluckman JL. Effects of hemimandibulectomy on quality of life. Laryngoscope. 1998;108:1574-1577.
FULL TEXT
|
ISI
| PUBMED
54. Kuntz AL, Weymuller EA. Impact of neck dissection on quality of life. Laryngoscope. 1999;109:1334-1338.
FULL TEXT
|
ISI
| PUBMED
55. Llewellyn-Thomas HA, Sutherland HJ, Thiel EC. Do patients' evaluations of a future health state change when they
actually enter that state? Med Care. 1993;31:1002-1012.
ISI
| PUBMED
56. Mantovani G, Ghiani M, Lai P, et al. Clinical evaluation of two dosages and schedules of ifosfamide in combination
with cisplatin in neo-adjuvant chemotherapy of patients with advanced (stage
III-IV) head and neck squamous cell carcinoma: a phase II randomized study. Oncol Rep. 1998;5:1499-1505.
ISI
| PUBMED
57. Hammerlid E, Mercke C, Sullivan M, Westin T. A prospective quality of life study of patients with oral or pharyngeal
carcinoma treated with external beam irradiation with or without brachytherapy. Oral Oncol. 1997;33:189-196.
ISI
| PUBMED
58. Rogers SN, Humphris G, Lowe D, Brown JS, Vaughan ED. The impact of surgery for oral cancer on quality of life as measured
by the Medical Outcomes Short Form 36. Oral Oncol. 1998;34:171-179.
FULL TEXT
|
ISI
| PUBMED
59. Rogers SN, Lowe D, Brown JS, Vaughan ED. A comparison between the University of Washington Head and Neck Disease-Specific
Measure and the Medical Short Form 36, EORTC QOQ-C33 and EORTC Head and Neck
35. Oral Oncol. 1998;34:361-372.
FULL TEXT
|
ISI
| PUBMED
60. Allison PJ, Locker D, Feine JS. The relationship between dental status and health-related quality of
life in upper aerodigestive tract cancer patients. Oral Oncol. 1999;35:138-143.
FULL TEXT
|
ISI
| PUBMED
61. de Graeff A, de Leeuw JR, Ros WJ, Hordijk GJ, Blijham GH, Winnubst JA. A prospective study on quality of life of patients with cancer of the
oral cavity or oropharynx treated with surgery with or without radiotherapy. Oral Oncol. 1999;35:27-32.
FULL TEXT
|
ISI
| PUBMED
62. Hammerlid E, Bjordal K, Ahlner-Elmqvist M, et al. Prospective, longitudinal quality-of-life study of patients with head
and neck cancer: a feasibility study including the EORTC QLQ-C30. Otolaryngol Head Neck Surg. 1997;116:666-673.
FULL TEXT
|
ISI
| PUBMED
63. Terrell JE, Nanavati K, Esclamado RM, Bradford CR, Wolf GT. Health impact of head and neck cancer. Otolaryngol Head Neck Surg. 1999;120:852-859.
FULL TEXT
|
ISI
| PUBMED
64. Allison PJ, Locker D, Wood-Dauphinee S, Black M, Feine JS. Correlates of health-related quality of life in upper aerodigestive
tract cancer patients. Qual Life Res. 1998;7:713-722.
FULL TEXT
|
ISI
| PUBMED
65. Chawla S, Mohanti BK, Rakshak M, Saxena S, Rath GK, Bahadur S. Temporal assessment of quality of life of head and neck cancer patients
receiving radical radiotherapy. Qual Life Res. 1999;8:73-78.
FULL TEXT
|
ISI
| PUBMED
66. Kreitler S, Chaitchik S, Rapoport Y, Kreitler H, Algor R. Life satisfaction and health in cancer patients, orthopedic patients
and healthy individuals. Soc Sci Med. 1993;36:547-556.
67. Chaturvedi SK, Shenoy A, Prasad KM, Senthilnathan SM, Premlatha BS. Concerns, coping and quality of life in head and neck cancer patients. Support Care Cancer. 1996;4:186-190.
FULL TEXT
|
ISI
| PUBMED
68. Curreli L, Lampis B, Santona MC, Mantovani G. Chemo-immunotherapy for advanced-stage malignancies and its impact
on quality of life: multidimensional evaluation in ten cancer patients. Support Care Cancer. 1996;4:462-464.
FULL TEXT
|
ISI
| PUBMED
69. Kaplan SH, Kravitz RL, Greenfield S. A critique of current uses of health status for the assessment of treatment
effectiveness and quality of care. Med Care. 2000;38:II184-II191.
70. Lohr KN, Aaronson NK, Alonso J. Evaluating quality-of-life and heath status instruments: development
of a scientific review criteria. Clin Ther. 1996;18:979-992.
FULL TEXT
|
ISI
| PUBMED
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