|Year : 2021 | Volume
| Issue : 1 | Page : 32-41
Measures that matter in head-and-neck cancer: Review of health-related quality of life
Sobin V Jacob1, Sharief K Sidhique1, Annie Jacob2, Jenifer Jeba2, Santam Chakraborty3, Balu Krishna Sasidharan1
1 Department of Radiation Oncology, Unit II, Christian Medical College, Vellore, Tamil Nadu, India
2 Department of Palliative Care Unit, Christian Medical College, Vellore, Tamil Nadu, India
3 Department of Radiation Oncology, Tata Memorial Centre, Kolkata, West Bengal, India
|Date of Submission||20-Aug-2020|
|Date of Decision||20-Aug-2020|
|Date of Acceptance||30-Sep-2020|
|Date of Web Publication||13-Jan-2021|
Dr. Balu Krishna Sasidharan
Department of Radiation Oncology, Unit II, Christian Medical College, Vellore - 632 002, Tamil Nadu
Source of Support: None, Conflict of Interest: None
In head-and-neck cancer (HNC), it is imperious to assess changes in health-related quality of life (HRQoL) for a comprehensive evaluation of patient needs and treatment outcomes. Currently, there is limited literature about HRQoL measures used in the Indian context. This lack of information may make it difficult for clinicians to understand their patients' overall well-being and hamper their ability to contrive the appropriate treatment plans. Several questionnaires are currently available and used to assess HRQoL in HNC. The objective of this review is to briefly reflect upon the available questionnaires in HNC, their availability in Indian regional languages and conceivable improvement in the design of the questionnaires, and their clinical use. This will allow the head-and-neck clinical team to compare and contrast the available questionnaires and make an informed choice about the most appropriate measure based on their study design or clinical workflow.
Keywords: Head-and-neck cancer, health-related quality of life, patient-reported outcome measures, virtual health care
|How to cite this article:|
Jacob SV, Sidhique SK, Jacob A, Jeba J, Chakraborty S, Sasidharan BK. Measures that matter in head-and-neck cancer: Review of health-related quality of life. Curr Med Issues 2021;19:32-41
|How to cite this URL:|
Jacob SV, Sidhique SK, Jacob A, Jeba J, Chakraborty S, Sasidharan BK. Measures that matter in head-and-neck cancer: Review of health-related quality of life. Curr Med Issues [serial online] 2021 [cited 2021 Apr 20];19:32-41. Available from: https://www.cmijournal.org/text.asp?2021/19/1/32/306933
| Background|| |
Survival outcomes and death rates continue to be the key indicators of population health for any disease condition, especially cancer. It was in the early 1990s that a paradigm shift happened when the WHO introduced the concept of health-related quality of life (HRQoL) that investigates beyond the direct measure of health-related conventional parameters. Since then, there has been increasing emphasis on the use and reporting of patient-reported outcome measures (PROMs) in regular cancer clinical practice. PROMs include reports that are directly provided by the patient about their health and treatment details and are measured using a self-reported measurement tool. These reports facilitate timely detection of patient distress and are used as a performance metric for assessing the quality of care.
It is in the early 2000s that the Institute of Medicine directed their health-care providers to deliver care that is safe, effective, prompt, systematic, just, and most importantly, patient oriented. Since then, it is quite evident that we can no longer concentrate solely on objective outcome data collected by providers. Focus has also been on developing measurement tools that can both largely and consistently capture factors that define health and affect outcome from the patient's perspective. The major stumbling block is that such concepts are very difficult to define, onerous to measure, and arduous to interpret.
Patient-centered outcome measures are not limited to global HRQoL impacts of health but may also include somatic symptoms, treatment-related adverse events, or psychosocial issues. There are two categories of PROMs, namely generic or disease-specific measures. While generic measures comprehensively evaluate the overall effects and are agnostic to patient population, disease, or treatment type, condition-specific measures are sensitive and capture-specific issues related to the disease. HRQoL, patient satisfaction, patient preference decision regret, etc., are the frequently reported patient-reported outcomes, with HRQoL being the most common PROM in clinical oncology.
In India, head-and-neck cancers (HNCs) contribute to 30% of all cancers. These include cancers of the oral cavity, larynx, hypopharynx, oropharynx, nasopharynx, nasal cavity, salivary glands, and paranasal sinuses. Combined modality approach with surgery, radiotherapy, and systemic therapy has improved survival outcomes in HNCs. Improvement in survival may be associated with higher prevalence of late treatment toxicity which also affects the quality of life. Since HNCs arise in anatomically complex and functionally important areas, both the disease and treatment often impair routine activities of daily living such as speech and ability to eat. This impacts the social interactions and psychological state of the patient. Such effects on the physical, psychosocial, and spiritual domains are less understood and rarely addressed in routine oncology practice. There are several validated generic and disease-specific measures available to measure HRQoL objectively in HNCs and forms the primary subject of this review.
| Defining Health-Related Quality of Life|| |
Heckscher coined the term “quality of life” (QoL), and in 1977, the United States National Library of Medicine incorporated it as a “keyword.” The phrase QoL means different things for each individual, making it a multifaceted global construct often defined by innate experiences and observations. Joyce and Mcgee described QoL as a measure of how good or bad life feels while the WHO defines it as a person's perception of their situation in life with respect to their goals, expectations, standards, and concerns within the framework of their culture and value systems., HRQoL is a specific subset of QoL introduced by the WHO in 1997 and is an abstract concept with many overlapping domains making it difficult to define as well as evaluate. According to the WHO, HRQoL defines the physical, mental, emotional domains and tries to qualitatively assess the social, cognitive sexual spiritual functionality of an individual. Hays et al. define it as how a person approaches life and perceives their physical, mental, and social well-being. HRQoL places emphasis on QoL that is related to and is affected by health or the lack of. Clinical parameters such as blood or scan reports and biological and physiological functions are not often included in the concept of HRQoL.
The conceptual model of linking clinical variables with QoL and thereby defining HRQoL was first developed by Wilson and Cleary. According to them, HRQoL is an output of various interconnected factors, namely general health condition of the individual, biological, and physiological variables including severity of symptoms, social and environmental characteristics, spiritual as well as psychological functioning of the individual, and economic support. These relationships, as conceptualized by them, are displayed schematically in [Figure 1].
|Figure 1: Revised Wilson and Cleary model for health-related quality of life. Adapted from “Linking clinical variables with health-related quality of life: A conceptual model of patient outcomes,” by I. B. Wilson and P. D. Clearly, 1995.|
Click here to view
In the model described by Wilson and Clearly [Figure 1], it is explicit that the concept of HRQoL is entwined between the individual and his environment. At each level, the concepts from left to right include other nonmedical factors that are difficult to measure and beyond the control of clinicians or health-care providers. Over the years, it has become evident that the best way to measure and document HRQoL is through systematic and comprehensive questionnaires which can address different components elaborated by the WHO or Wilson and Cleary model.
Questionnaires are the backbone of PROMs, but many qualitative tools are also available. PROMs that encapsulate the effect of cancer and treatments on health outcomes on the individual as a whole have been developed and validated by various oncology groups across the world in different languages. Studies have confirmed that patients who took the HRQoL questionnaires developed a better rapport with their health-care providers and were satisfied about treatment leading to an improvement of their subsequent HRQoL scores. Understanding the trajectory of change in HRQoL is vital for gathering patient data and shared decision-making. HRQoL measures are important both during radical treatment and palliative care. Specific problems may be identified with HRQoL questionnaires during follow-ups, and it helps to incorporate supportive care early and appropriate to the needs of the patient. Hence, to better assess treatment outcomes, understanding the changes in HRQoL that follow as a result of the disease, treatment, or any other issues is key.
| Health-Related Quality of Life in Head-and-Neck Cancer Patients – Why?|| |
Pain is common in HNCs in addition to problems related to airway and swallowing. These problems are often exacerbated by treatments such as surgery and radiotherapy. Approximately, two-thirds of the HNC patients develop severe oral mucositis during radiotherapy often leading to but not limited to difficulty in swallowing and tasting, vocal problems, excessive oropharyngeal secretions, halitosis, disturbed sleep, and pain. Xerostomia is caused due to injury to the salivary glands and altered production of saliva causing pain, difficulty in swallowing, eating, oral infections, dental caries, compromised speech, etc.,, High toxicity load associated with HNC treatment can immensely impact HRQoL. Unfortunately, most of these are subjective issues, and evidence suggests that their magnitude is often overlooked or underestimated.
However, in oncology randomized controlled trials (RCTs), the need for PROMs is gradually recognized. Of the recent oncology trials, an estimated 29% have included a PRO endpoint. Rogers et al. mention the major issues that affect HRQoL in HNC that needs special mention., Some of it is depicted in [Figure 2].
|Figure 2: Major issues that affect health-related quality of life in head-and-neck cancer.|
Click here to view
The patient-reported outcome evaluation is critical in clinic setting, and also in RCTs to provide potent, evidence-based symptom management, rehabilitation, and supportive care, HRQoL assessment in HNC is critical to evaluate treatment and to develop rehabilitative services and informational material for patients.
| Health-Related Quality of Life and Survival in Head-and-Neck Cancers – Correlation Analysis|| |
Quinten et al. studied the relationship between pretreatment HRQoL and survival in 11 different cavncers and reported that for each cancer, HRQoL domains added prognostic information over and above that was provided by age, gender, and performance status. The systematic review by van Nieuwenhuizen et al. reported that higher pretreatment physical functioning score was associated with increased survival with a strong correlation between change in global QoL (from pretreatment to 6 months posttreatment) and improved survival. However, the association of survival with other pretreatment HRQoL subscales such as global QoL, mental HRQoL, emotional, role, cognitive, and social functioning has very limited evidence. A strong correlation between cognitive functioning and survival was reported based on a single study. Single men without family support and poor socioeconomic background had poor survival but not proven significance in RCTs.
Obviously, more studies are required to establish any relationship between emotional or cognitive function and survival. Future studies should also aim to include HRQoL evaluation at different time points posttreatment to improve its predictive value.
| Assessment of Health-Related Quality of Life – How?|| |
HRQoL is by typically questionnaires answered by patients (quantitative); open and semi-structured interview (qualitative) methods have also been reported. None of the questionnaires are the gold standard, with each having its own pros and cons. Both longitudinal and cross-sectional questionnaires are used. In longitudinal questionnaires, the assessment starts from pretreatment period to provide a trajectory of the change during the course of the disease. However, compliance, patient dropouts, and testing effects bring additional challenges to the interpretation. Cross-sectional evaluation refers to doing an evaluation at a particular time point which can be repeated subsequently, if indicated. Although it is simpler to conduct, it lacks the temporal information that longitudinal studies provide. Cross-sectional studies also have stringent population selection criteria to be valid such that all the patients are measured at the same point during the course of their disease.
| Tools Available for Health-Related Quality of Life|| |
Despite all the challenges amid moving from bench side to clinic over the past two decades, there are many tools available for measuring HRQoL in a systematic, pragmatic, and scientific manner. These tools, as depicted in [Figure 3], are broadly classified as generic or specific.
|Figure 3: Some examples of generic and specific scales for health-related quality of life assessment.|
Click here to view
Generic scales focus on the overall health of the patient. Generic measure of QoL covers 7 main domains that include physical, social-emotional, and overall well-being, cognitive function, pain symptoms, and vitality. Some of the commonly used generic questionnaires are mentioned in [Table 1].
Specific scales include only specific elements that are possibly affected by the disease or its treatment. We will discuss some of the widely used and accepted questionnaires.
The disease-specific scales available for cancer are listed in [Table 2]. The two popular cancer-specific assessment measures are the EORTC QLQ-C30 and Functional Assessment of Cancer Therapy General (FACT-G). A systematic review by Luckett et al. showed that studies that focused on the financial impact and physical symptoms of cancer treatment used EORTC QLQ-C30 while those that reported HRQoL or had limited sample sizes used the FACT-G questionnaire.
There are 19 tools that have been validated and available to evaluate head-and-neck disease-related well-being and functional status. These tools were targeted toward patients with HNC, some of them specifically for nasopharyngeal and parotid tumors, skin cancers, and thyroid cancers.
Often physical functions (taste, nutrition, constipation, pain, articulation, dysphagia, disfigurement, xerostomia, and upper-body mobility), psychosocial functioning, and treatment/decision regret are included as the parameters of interest. The assessment time frame ranges from “today” to the “previous 4 weeks.”
EORTC-HN35 and FACT-HN40 are the two widely accepted site-specific tools available for routine use and research. Other tested instruments in this category are discussed in [Table 3].
Eleven tools have been validated till date and used routinely to assess the treatment-related side effects of radiation therapy, chemotherapy, and surgery. Various domains covered by these tools include physical functioning (site-specific physical symptoms, appearance, recreation, activity, fatigue, sleep, concentration, pain, and digestion), psychosocial functioning (including socioeconomic concerns), and satisfaction. The assessment time frame ranges from “previous 24 h” to more vague ones such as “everyday life” and “since therapy.”
Most utilized instruments are QoL Radiation Therapy Index (QoL-RTI), Neck Dissection Impairment Index, and Shoulder Pain and Disability Index. However, these instruments have limited clinical presence and very limited data available in published literature. Only cross-cultural adaptationis the Chinese version available for QoL-RTI [Table 4].
Most of the questionnaires in this category were designed to assess physical (pain, mucositis, xerostomia dysphagia, voice, and disfigurement) and psychosocial issues. Hence, the time frame of assessment ranged from “at the present moment” to time since the onset of a particular symptom. Minimal clinically important difference or normative data have been used to interpret total and subscale scores. The most commonly tested and used instruments are discussed in [Table 5].
The fear of cancer recurrence (FCR) is an overwhelming factor that commonly affects HRQoL of cancer survivors. Hence, the assessment of FCR is crucial for understanding their psychological state. There are some validated questionnaires available to assess patients' fears and worries. The Cancer Worry Scale is a tool capable of detecting high levels of fear FCR and helps to provide appropriate psychological assistance to survivors at the earliest. Other recently validated questionnaires are the FCR7 which is a seven-question self-report scale and FCR4 which is a shorter version of the FCR7.,
It is unclear how motivation to seek medical care affects HRQoL of patients. It is an evolving area of research, and some centers have already validated questionnaires for clinical use. Examples include Achievement Motive Index for Medical Treatment (AMI-MeT), which comprises of self-Derived Achievement Motivation (AMS), Achievement Motivation derived from Others (AMO) and Apter Motivational Style Profile.,
Duke's Religious Index and Santa Clara Strength of Religious Faith Questionnaire assess the religious involvement in cancer patients and HRQoL outcomes., However, these questionnaires are not in wide use.
| How to Choose the Right Questionnaire?|| |
There are innumerable validated questionnaires freely available in different languages. Often, choosing the right one is cumbersome and should be done in view of the specific research planned. Therefore, a researcher should give thought to the following attributes before choosing a particular questionnaire for a research study or clinical practice. Some of the attributes of an ideal questionnaire are mentioned in [Figure 4]. In light of these special attributes, future designing of HRQoL questionnaires should be such that it is both a comprehensive and flexible tool. If a particular questionnaire is not available in regional languages, it is always better to get it translated to make it more culturally adaptable even though it is a tedious process. The first step in cultural adaptation of a questionnaire to a regional language is to seek permission from the original authority or from the copyright owner, followed by linguistic translation (requires multiple linguistic experts proficient in different languages) and psychometric validation. Some of the standard questionnaires come with guidelines for translation and validation, usually employing two or more forward translations by multiple independent translators followed by a reverse translation to original language followed by testing on a small cohort of patients.
Unfortunately, there is yet no “gold standard” or “all-encompassing” questionnaire that possesses all of these attributes. Hence, it is imperative that researchers study psychometric properties as well as the study design and objectives to better understand the benefits and pitfalls of combining different measures.
| Difficulties in Implementation in Routine Clinical Practice|| |
There has been an incredible growth noted in the assessment of HRQoL in HNC studies over the past two decades. At the same time, there is huge variability in design and lack of consolidated universal reporting standards that make pooling of data from different sources cumbersome and difficult to generalize for clinical decision-making. Furthermore, the clinical translation is limited as the clinicians are not familiar with the properties of available tools to make an informed choice on the best tool suited to their specific research or patient care. An area of serious concern is the lack of time for clinicians to establish rapport and then discuss HRQoL questionnaires with their patients. To overcome this barrier, trained head-and-neck nurses or physician assistants can be dedicated to this task. In a quasi-experimental prospective trial by De Leeuw et al., they reported that nurse-led sessions for HNC patients had a positive effect, especially in their HRQoL.
Although many recent studies and publications incorporate the HRQoL data, a vast majority of it is based on questionnaires directed exclusively at the patient. However, we think that the caregiver's views are equally important as the patients', since the caregiver plays a critical role in the patient's life. At the same time, any differences in QoL scores between these two groups may mean that an aspect of their care is being underreported.
Meanwhile, there are many inherent weaknesses associated with questionnaire-based HRQoL measure. Patients experience a wide variety of problems ranging in intensities at different times which cannot be completely evaluated either by cross-sectional or longitudinal methods. Furthermore, each questionnaire is restricted by the number and content of items included, most importantly the time frame (some ranges from a week to 4 weeks past the date of filling questionnaire). This can lead to or add misinterpretation and recall biases and response shift.
Collecting large volumes of patient data at different time points come with the massive responsibility of its safe storage for privacy concerns, ethical values, and ease at which data can be retrieved at any time for analysis or comparison. With the advent of Big Data Technology in health care, data collection, storage, analysis and sharing of information with different groups across the globe has become easier and hassle free.,
| Can Health-Related Quality of Life Get Incorporated into Virtual Health care?|| |
Recent technological developments can support data collection and analysis of patient-reported outcomes in a long way. Since most patients own mobile phone, many developer-clinical research partners have explored the possibilities in developing “Apps” that can send alerts to patients for HRQoL updates on certain features. However, administering QoL measures over the computer can overcome some of the limitations of administering paper-based questionnaires, digital data storage, and reduce workforce requirements. Interactive-voice-response-system can also be incorporated into routine practice so that QoL questionnaires can be administered to patients over the telephone. The potential to make questionnaire information immediately available on devices would be an important factor to make clinicians enthusiastic and thereby transform patient care.
Many web applications of the like of Facebook, WhatsApp etc., (with modified patients' privacy protection norms) can include standardized questions at select time points (once a day or once a week) which would score the patient's generic, specific, or global well-being. This could be stored in a repository and be accessed by a clinician with required permissions. This future model may help limit recall bias and would lead to real-time monitoring similar to virtual health platforms currently available for chronic diseases like diabetes.
Although these technological advancements offer an exciting possibility, it is still in its infancy. It offers a comprehensive and flexible technique to gather information about the HRQoL that will allow us to explore, study, and intervene in a much better way.
| Conclusion|| |
The ramifications of HNC diagnosis on the person and the aftermath of its treatment spread over multiple functional domains and can have a direct influence on the posttreatment HRQoL. Length of survival alone is an inadequate measure of treatment success, rather it is the quality of survival that needs to be assessed and enhanced. This is possible only with the support of a multidisciplinary team consisting of doctors, specialist nurses, psychologists, physiotherapists and occupational therapists.
With time HRQoL has progressed and unfolded into a better organized and scientific discipline, however finding its association with survival is far more beneficial. There are many validated generic and specific scales for estimating HRQoL at present which have their merits and demerits. Most of the commonly used questionnaires have been translated and validated in various Indian languages as well. Advances in information technology have the potential to allow easier implementation and facilitate better decision-making. Problem areas can be identified with more clarity, and information regarding HRQoL can be delivered to various groups with an aim to derive interventions that improve the HRQoL outcomes.
BS would like to thank Dr. H Thomas for technical editing, language editing, and proofreading this manuscript.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
The World Health Organization Quality of Life Assessment (WHOQOL): Position paper from the World Health Organization. Soc Sci Med 1995;41:1403-9.
Howell D, Molloy S, Wilkinson K, Green E, Orchard K, Wang K, et al
. Patient-reported outcomes in routine cancer clinical practice: A scoping review of use, impact on health outcomes, and implementation factors. Ann Oncol 2015;26:1846-58.
Institute of Medicine (US) Committee on Quality of Health Care in America. Crossing the Quality Chasm: A New Health System for the 21st
Century. Washington (DC): National Academies Press (US); 2001. Available from: http://www.ncbi.nlm.nih.gov/books/NBK222274/
. [Last accessed on 2020 Jun 03].
Lipscomb J, Gotay CC, Snyder CF. Patient-reported outcomes in cancer: A review of recent research and policy initiatives. CA Cancer J Clin 2007;57:278-300.
Sharma JD, Baishya N, Kataki AC, Kalita CR, Das AK, Rahman T. Head and neck squamous cell carcinoma in young adults: A hospital-based study. Indian J Med Paediatr Oncol 2019;40:18. [Full text]
Melo Filho MR, Rocha BA, Pires MB, Fonseca ES, Freitas EM, Martelli Junior H, et al
. Quality of life of patients with head and neck cancer. Braz J Otorhinolaryngol 2013;79:82-8.
de Haes J, Curran D, Young T, Bottomley A, Flechtner H, Aaronson N, et al
. Quality of life evaluation in oncological clinical trials-The EORTC model. The EORTC Quality of Life Study Group. Eur J Cancer 2000;36:821-5.
Morton RP. Evolution of quality of life assessment in head and neck cancer. J Laryngol Otol 1995;109:1029-35.
Burckhardt CS, Anderson KL. The quality of life scale (QOLS): Reliability, validity, and utilization. Health Qual Life Outcomes 2003;1:60.
McGee HM, O'Boyle CA, Hickey A, O'Malley K, Joyce CR. Assessing the quality of life of the individual: The SEIQoL with a healthy and a gastroenterology unit population. Psychol Med 1991;21:749-59.
Rogers SN, Semple C, Babb M, Humphris G. Quality of life considerations in head and neck cancer: United Kingdom national multidisciplinary guidelines. J Laryngol Otol 2016;130:S49-S52.
Saxena S, Orley J, WHOQOL Group. Quality of life assessment: The world health organization perspective. Eur Psychiatry 1997;12:263s-6s.
Hays RD, Reeve BB. Measurement and Modeling of Health-Related Quality of Life, 2008, DOI: 10.1016/B978-012373960-5.00336-1.
Ebrahim S. Clinical and public health perspectives and applications of health-related quality of life measurement. Soc Sci Med 1995;41:1383-94.
Wilson IB, Cleary PD. Linking clinical variables with health-related quality of life. A conceptual model of patient outcomes. JAMA 1995;273:59-65.
Asadi-Lari M, Tamburini M, Gray D. Patients' needs, satisfaction, and health related quality of life: Towards a comprehensive model. Health Qual Life Outcomes 2004;2:32.
Ferrans CE, Zerwic JJ, Wilbur JE, Larson JL. Conceptual model of health-related quality of life. J Nurs Scholarsh 2005;37:336-42.
Cheng KK, Leung SF, Liang RH, Tai JW, Yeung RM, Thompson DR. Severe oral mucositis associated with cancer therapy: Impact on oral functional status and quality of life. Support Care Cancer 2010;18:1477-85.
Chambers MS, Garden AS, Kies MS, Martin JW. Radiation-induced xerostomia in patients with head and neck cancer: Pathogenesis, impact on quality of life, and management. Head Neck 2004;26:796-807.
Peach MS, Trifiletti DM, Vachani C, Arnold-Korzeniowski K, Bach C, Hampshire M, et al
. Patient-reported outcomes in head and neck cancer: Prospective multi-institutional patient-reported toxicity. Patient Relat Outcome Meas 2018;9:245-52.
Vodicka E, Kim K, Devine EB, Gnanasakthy A, Scoggins JF, Patrick DL. Inclusion of patient-reported outcome measures in registered clinical trials: Evidence from ClinicalTrials.gov (2007-2013). Contemp Clin Trials 2015;43:1-9.
Chandu A, Smith AC, Rogers SN. Health-related quality of life in oral cancer: A review. J Oral Maxillofac Surg 2006;64:495-502.
Quinten C, Martinelli F, Coens C, Sprangers MA, Ringash J, Gotay C, et al
. A global analysis of multitrial data investigating quality of life and symptoms as prognostic factors for survival in different tumor sites. Cancer 2014;120:302-11.
van Nieuwenhuizen AJ, Buffart LM, Brug J, Leemans CR, Verdonck-de Leeuw IM. The association between health related quality of life and survival in patients with head and neck cancer: A systematic review. Oral Oncol 2015;51:1-11.
Mehanna HM, De Boer MF, Morton RP. The association of psycho-social factors and survival in head and neck cancer. Clin Otolaryngol 2008;33:83-9.
Du XL, Lin CC, Johnson NJ, Altekruse S. Effects of individual-level socioeconomic factors on racial disparities in cancer treatment and survival: Findings from the national longitudinal mortality study, 1979-2003. Cancer 2011;117:3242-51.
Jones SM, Shulman LJ, Richards JE, Ludman EJ. Mechanisms for the testing effect on patient-reported outcomes. Contemp Clin Trials Commun 2020;18:100554.
Laraway DC, Rogers SN. A structured review of journal articles reporting outcomes using the University of Washington quality of life scale. Br J Oral Maxillofac Surg 2012;50:122-31.
Humphris GM, Watson E, Sharpe M, Ozakinci G. Unidimensional scales for fears of cancer recurrence and their psychometric properties: The FCR4 and FCR7. Health Qual Life Outcomes 2018;16:30.
Hatta T, Narita K, Yanagihara K, Ishiguro H, Murayama T, Yokode M. Measuring motivation for medical treatment: Confirming the factor structure of the Achievement Motivation Index for Medical Treatment (AMI-MeT). BMC Med Inform Decis Mak 2016;16:22.
Cuevas BT, Hughes DC, Parma DL, Treviño-Whitaker RA, Ghosh S, Li R, et al
. Motivation, exercise, and stress in breast cancer survivors. Support Care Cancer 2014;22:911-7.
Sherman AC, Plante TG, Simonton S, Adams DC, Harbison C, Burris SK. A multidimensional measure of religious involvement for cancer patients: The duke religious index. Support Care Cancer 2000;8:102-9.
Plante TG, Boccaccini MT. The santa clara strength of religious faith questionnaire. Pastor Psychol 1997;45:375-87.
Menon D, Venkateswaran C. The process of translation and linguistic validation of the functional assessment of cancer therapy-brain quality of life instrument from English to Malayalam: The challenges faced. Indian J Palliat Care 2017;23:300-5.
] [Full text]
Sayed SI, Elmiyeh B, Rhys-Evans P, Syrigos KN, Nutting CM, Harrington KJ, et al
. Quality of life and outcomes research in head and neck cancer: A review of the state of the discipline and likely future directions. Cancer Treat Rev 2009;35:397-402.
De Leeuw J, Prins JB, Teerenstra S, Merkx MAW, Marres HAM, van Achterberg T. Nurse-led follow-up care for head and neck cancer patients: a quasi-experimental prospective trial. Supportive Care in Cancer. [Online] 2013;21:537–47.
La Mantia I, Rossitto F, Andaloro C. Quality of life in head and neck cancer: Patients' and family caregivers' perceptions. Egypt J Ear Nose Throat Allied Sci 2017;18:247-50.
Willems SM, Abeln S, Feenstra KA, de Bree R, van der Poel EF, Baatenburg de Jong RJ, et al
. The potential use of big data in oncology. Oral Oncol 2019;98:8-12.
Wilkie JR, Mierzwa ML, Yao J, Eisbruch A, Feng M, Weyburne G, et al
. Big data analysis of associations between patient reported outcomes, observer reported toxicities, and overall quality of life in head and neck cancer patients treated with radiation therapy. Radiother Oncol 2019;137:167-74.
[Figure 1], [Figure 2], [Figure 3], [Figure 4]
[Table 1], [Table 2], [Table 3], [Table 4], [Table 5]