Abstract
The purpose of this review was to identify cross-cultural and psychometric characteristics of the European Organization for Research and Treatment of Cancer Head and neck cancer questionnaire (EORTC QLQ-H&N35) in various languages. A literature search was performed for original papers in PubMed, EMBASE, and Google scholar electronic databases on validation, psychometric properties of the EORTC-H&N35 questionnaire for patients with head and neck cancer. A total of 17 papers had been reviewed systematically. The studies were conducted in 28 countries and EORTC QLQ-H&N35 questionnaire was validated in 21 different languages. The majority of papers reported high reliability having Cronbach's coefficient above 0.70. Low reliability was reported for senses and speech problems, pain, and less sexuality. Moderate to good convergent validity was found as the correlation coefficient was above 0.40 except for speech problems and social contact trouble. Discriminant validity (weak correlations < 0.70) was confirmed in 14 papers. This review provides comprehensive information on cross-cultural and psychometric properties of EORTC QLQ-H&N35 and can be recommended to implement in oncological practice.
Keywords: Head and neck cancer, Validation, Psychometrics, Quality of life, Questionnaires
Introduction
Head and neck cancer (HNC) is a significant public health challenge that affects several world regions. Globally, head and neck cancer account for more than 6,50,000 cases and 3,30,000 deaths annually [1]. In spite of multiple modalities of treatment such as surgery, radiation, and chemotherapy has achieved better results in recent decades, providing a significant increase in patient survival for HNC survivors and the impact of treatment on quality of life (QoL) [2, 3]. Hence, for such patients, survival from the diseases and the QoL is equally essential. Patient-reported QoL questionnaire has been used as a clinical outcome measurement to encompass a patient’s perception of his or her emotional, physical, social, and sexual state, which indicates the overall well-being of patients [4].
Quality of life has usually been assessed through questionnaires. Questionnaires can help to evaluate quality of life, which mainly consists of four primary domains -physical, social, emotional, and mental. Recently multiple questionnaires have been developed and validated to assess QoL in HNC patients. These questionnaires vary in recording responses and can range from general questions such as physical, social, and psychological questions to specific functional performance such as swallowing, speech, xerostomia [5, 6]. Most widely used questionnaires in head and neck cancer patients include the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 (EORTC QLQ-C30), the Head and Neck 35 (EORTC QLQ-H&N35), the Head and Neck Radiotherapy Questionnaire (HNRQ), the University of Michigan Head and Neck Quality of Life Questionnaire (HN-QOL), Functional Assessment of Cancer Therapy-Head and Neck (FACT-H&N) and the University of Washington Head and Neck Disease-Specific Measure (UW-QOL)[7].
European Organization for Research and Treatment of Cancer Quality of Life group [8] developed a site-specific questionnaire EORTC QLQ-H&N35 for HNC patients which is used along with core questionnaire EORTC QLQ-C30. The questionnaire has been translated into 73 languages and is used as one of the standard instruments for measuring QoL in HNC patients [9]. The EORTC QOL-H&N35 consists of 35 questions. Out of 35 questions, 18 questions are symptom-based, 12 questions related to function which scored on a four-point Likert scale from 1 (not at all) to 4 (very much), while five questions related to pain, supplemental feeding, and weight are scored on a dichotomous scale 0 (no) and 1 (yes) [10].
Currently, assessment of QoL in HNC patients remains a research question and also the use of EORTC QLQ-H&N35 in context with the psychometric issues related to multi-item scales in different languages is not be identified. Hence, the purpose of this paper was to identify the literature on validation of the EORTC QLQ-H&N35 questionnaire in different languages (cross-cultural uses) to date, review systematically and assess the psychometric characteristics (reliability and validity) of multi-item scales of EORTC QLQ-H&N35.
Materials and Methods
Preferred Reporting Items for Systematic reviews and Meta-Analysis (PRISMA) guidelines [11] were taken into consideration to conduct the current systemic review.
Searching the Literature
A literature search was carried out using PubMed, EMBASE, and Google Scholar electronic databases. The keywords and medical subject headings included the combination of validation, psychometric properties, head and neck cancer, laryngeal cancer, quality of life, and EORTC H&N35. These words can appear in the title and/or abstract and in all fields of publication. The literature search was done for full articles published only in the English language from 1992 to October 2020. The year 1992 was chosen because the first study to assess the QoL in HNC was published in that year [12].
Eligibility Criteria
All observational studies which fall under pre-decided inclusion and exclusion criteria were eligible for this systematic review. The inclusion criteria were: (1) cross-sectional studies, case–control studies, and cohort studies, (2) studies reporting on QoL in HNC, (3) validation of EORTC QLQ-H&N35 questionnaire studies assessing reliability (Cronbach’s α) and construct validity (convergent validity and discriminant validity) and (4) Publications in the English language, even if they are in the pre-publication stage were included. The exclusion criteria were: (1) review studies, (2) validation of questionnaires other than EORTC QLQ-H&N35 were excluded.
Data Collection and Extraction
Two reviewers (PS and SA) independently search for the title with validation and psychometric properties through the electronic search. Based on the above-mentioned eligibility criteria, a full-text evaluation was performed. The selected papers' eligibility was compared and discussed between the two reviewers, and the final decision was made. Kappa statistics determined the inter-rater reliability between the two reviewers.
The data were extracted from selected papers using a pre-formatted sheet with a set of pre-defined parameters like: (1) study characteristic (principal investigator, year of publication, and study design), (2) study subject characteristic (study place, sample, and demographic of subjects), (3) HNC characteristic (site of cancer and treatment modalities) and (4) psychometric characteristic- reliability (Cronbach’s α) and construct validity (convergent validity and discriminant validity).
Results
The selection of papers for review as per PRISMA guidelines is shown in Fig. 1. Total of 648 articles were obtained by searching in various databases. Out of these, 519 papers were found to be duplicates; hence, 129 papers were screened for the study's title and description. A total of 33 articles match the title and description of the study. After considering the predetermined eligibility criteria, 16 papers were excluded. Hence, at last, 17 papers were included in this systematic review. The agreement between the two reviewers has a κ value of 0.86, which indicates strong agreement. Total 17 papers included were published from 1999 to 2020 and are summarized in chronological order in the Table 1.
Fig. 1.
PRISMA flowchart for paper selection
Table 1.
Summary of reviewed papers
| Author Name (Year of publication) | Country- Language | Sample size | Demographic of subject | Site of Cancer | Treatment | Reliability (Cronbach alpha coefficient) | Validity |
|---|---|---|---|---|---|---|---|
| Bjordal K et al. (1999) [13] | 3 countries- Norwegian, Swedish, Dutch | 500 | Mean age: 61 years, Male: 372 (74.40%); Female: 27 (25.60%) | Larynx: 30%, Oral cavity:39% | S, RT, CT and/or combination | 0.78 (pain and swallowing) to 0.87 (speech); 0.10 (senses problem) | Convergent validity: Spearman’s correlation coefficient range: 0.40–0.69. Discriminant validity: week correlation coefficient < 0.70 |
| Sherman AC et al. (2000) [15] | Arkansas- English | 160 | Mean age: 57 ± 14.40 years, Male: 104 (65.0%); Female: 56 (35.0%) | Larynx: 22%, Oral cavity: 18% | S, RT, CT and/or combination | 0.75 (problem with speech) to 0.93 (less sexuality); 0.54 (senses problem) | Discriminant validity: Spearman’s correlation coefficient < 0.70; > 0.70 (between trouble with social eating and problem in speech) |
| Bjordal K et al. (2000) [8] | 12 countries- Norwegian, Swedish, Dutch, English, Finnish, French, Spanish, German, Polish | 622 | Median age: 63 years, Male: 505 (81.18%); Female: 117 (18.82%) | Larynx: 47.11% Oral cavity: 30.71% | S, RT, CT and/or combination | 0.72 (speech problem) to 0.95 (less sexuality) | Discriminant validity: Spearman’s correlation coefficient < 0.70; > 0.70 (between problem with swallowing and speech problem) |
| Zotti P et al. (2001) [16] | Italy-Italian | 99 | Mean age: 67 years, Male: 86 (87%); Female: 13 (13%) | Larynx: 100% | S, RT, CT | 0.72 (pain) to 0.90 (less sexuality); 0.58 and 0.53 for senses problem and speech problems respectively | Convergent validity: Spearman’s correlation coefficient range: 0.46–0.95. Discriminant validity: week correlation coefficient < 0.70 |
| Chaukar DA et al. (2005) [38] | India-Hindi | 200 | Male: 148 (74%); Female:52 (26%) | Larynx: 12.00% Oral pharynx: 68% | S | 0.70 (senses problem) to 0.92 (trouble with social eating) | Convergent validity: Pearson’s correlation coefficient > 0.40. Discriminant validity: week correlation coefficient < 0.70 |
| Toth G et al. (2005) [22] | Japan-Japanese | 108 | Mean age: 68.80 ± 8 years, Male: 97 (89.80%); Female: 11 (10.20%) | Larynx: 100% | S | 0.70 (senses problem) to 0.93 (less sexuality); 0.64 (pain) | Convergent validity: Pearson’s correlation coefficient range: 0.55–0.82. Discriminant validity: week correlation coefficient < 0.70 |
| Jensen K et al. (2006) [23] | Denmark- Danish | 116 | Mean age: 62 years, Male: 74 (64.0%); Female: 42 (36.0%) | Larynx: 38%, Oral cavity:33% | S, RT | 0.82 (problem with swallowing) to 0.93 (Less sexuality) | Discriminant validity: Spearman’s correlation coefficient < 0.70; > 0.70 (between trouble with social eating and problem in swallowing) |
| Singer S et al. (2009) [21] | Germany-German | 323 | Mean age: 65.10 ± 9.60 years, Male: 296 (91.60%); Female: 27 (8.40%) | Larynx: 100% | S, RT | 0.70 (problem with senses) to 0.90 (less sexuality); 0.55 (speech problem) | Convergent validity: Pearson’s correlation coefficient range: 0.13–0.83. Discriminant validity: week correlation coefficient < 0.70; > 0.70 (between problem in swallowing and other scales) |
| Bower WF et al. (2009) [17] | Hong Kong- Cantonese | 119 | Median age: 61 years, Male: Female ratio: 3.01:1 | Larynx: 20.30% Oral cavity: 46.40% | RT, CT | 0.80 (pain) to 0.95 (Less sexuality); 0.34 (senses problem) | Convergent validity: Pearson’s correlation coefficient range: 0.61–0.98. Discriminant validity: week correlation coefficient < 0.70 |
| Jayasekara H et al. (2009) [18] | Sri Lanka-Sinhala | 196 | Male: 150 (76.50%); Female: 46 (23.50%) | Pharynx:24.50% Oral cavity: 70.0% | S, RT, CT and/or combination | 0.73 (pain) to 0.89 (trouble in social contact); 0.61 and 0.60 for senses problem and less sexuality respectively | Convergent validity: Pearson’s correlation coefficient range- 0.40–0.84. Discriminant validity: week correlation coefficient < 0.70; > 0.70 (social eating) |
| Nalbadian M et al. (2010) [14] | Greece- Greek | 109 | Median age: 62.57 years, Male: 98 (88.10%); Female: 13 (11.90%) | Larynx: 80.70% Oral pharynx: 19.30% | S, RT, CT and/or combination | 0.73 (trouble with swallowing) to 0.99 (less sexuality); 0.23 (senses problem) | Convergent validity: Spearman’s correlation coefficient range: 0.42–0.99. Discriminant validity: week correlation coefficient < 0.70 |
| Yang Z et al. (2012) [26] | China- Chinese | 133 | Mean age: 52.0 ± 15.4 years, Male: 98 (73.70%); Female: 35 (26.30%) | Head and neck | S, RT, CT and/or combination | 0.71 (less sexuality) to 0.83 (speech problem and trouble with social eating) | Convergent validity: Pearson’s correlation coefficient range: 0.64–0.94. Discriminant validity: week correlation coefficient < 0.70; > 0.70 (between items of pain, problem in swallowing, trouble with social contact and eating) |
| Carrillo JF et al. (2013) [19] | Mexico- Mexican Spanish | 193 | Mean age: 56.90 years, Male:104 (53.89%); Female: 89 (46.11%) | Larynx: 18.10%, Oral cavity: 23.30% | RT, CT | 0.75 (pain, less sexuality) to 0.84 (swallowing and social eating); 0.49 and 0.62 for senses problem and speech problem respectively | Convergent validity: Spearman’s correlation coefficient range- 0.16–0.67. Discriminant validity: week correlation coefficient < 0.70 |
| Tomaszewska IM et al. (2013) [24] | Poland- Polish | 51 | Mean age: 51.30 ± 12.90 years, Male: 28 (54.90%); Female: 23 (45.10%) | Head and neck | S, RT, CT and/or combination | 0.71 (less sexuality) to 0.87 (trouble in social eating) | Convergent validity: Spearman’s correlation coefficient range: 0.33–0.83. Discriminant validity: week correlation coefficient < 0.70 |
| Ouattassi N et al. (2015) [37] | Morocco- Arabic | 120 | Mean age: 57 ± 16 years, Male: 73 (60.50%); Female: 47 (39.50%) | Larynx: 45.20%, Oral cavity:14.40% | S, RT, CT and/or combination, Palliative | 0.71 (trouble with social contact) to 0.94 (senses-taste and speech problems) | Convergent validity: Spearman’s correlation coefficient range: 0.72–0.98. Discriminant validity: week correlation coefficient < 0.70 |
| Kucharska E et al. (2016) [25] | Poland- Polish | 176 | Mean age: 51.30 ± 11.20 years, Male: 94 (53.41%); Female: 82 (46.59%) | Head and neck | S, RT, CT and/or combination | 0.71 (less sexuality) to 0.87 (trouble in social eating) | Convergent validity: Spearman’s correlation coefficient range: 0.31–0.85. Discriminant validity: week correlation coefficient < 0.70 |
| Parkar S et al. (2020) [20] | India- Gujarati | 400 | Mean age: 45.47 ± 10.31 years, Male: 350 (87.50%); Female: 50 (12.50%) | Larynx: 8.50%, Oral cavity: 85% | S, RT, CT and/or combination | 0.71 (trouble with social contact) to 0.77 (less sexuality); 0.69 and 0.68 for senses problem and speech problem respectively | Convergent validity: Spearman’s correlation coefficient range: 0.42–0.94. Discriminant validity: week correlation coefficient < 0.70 |
Bold letters indicate exception values of coefficient (Reliability: Cronbach’s alpha below 0.70 and Discriminant validity: correlation coefficient above 0.70). S = Surgery, RT = Radiotherapy, CT = Chemotherapy
Cross-cultural use All 17 papers reviewed showed the studies had a cross-sectional design. Out of the 17 papers reviewed, nearly half of studies 8 (47%) were conducted in European countries, 6 (35%) studies conducted in Asian countries, one study (18%) each in the United States and African country and Mexico.
Characteristic of study participants Total numbers of participants of the selected papers were 3625 ranging from 51 to 622, with a mean sample size of 213.24 ± 157.35. There was a male predominance in all the studies. Most of the studies had participants above 50 years of age. Cancer of the oral cavity and larynx are the common site involving the head and neck region having multiple treatment modalities, including surgical, radiotherapy, chemotherapy, and/or combinations of this treatment.
Psychometric characteristics Reliability in all the papers was found high, as Cronbach's coefficient is above 0.70. The Cronbach’s α coefficient reported in the selected papers ranges from 0.10 for senses problem [13] to 0.99 for less sexuality [14]. Low reliability (< 0.07) was reported with senses problems [13–20], speech problems [16, 19–21], pain [22] and less sexuality [18].
Out of 17 papers, 14 (82%) papers reported both convergent and discriminant validity, while the remaining three papers [8, 15, 23] had performed only discriminant validity. Moderate to good convergent validity was found for items, as supported by the item scale correlation coefficient above 0.40. Two papers [19, 21] had a low correlation coefficient of 0.13 and 0.16 with speech problems, while two papers from Poland [24, 25] had a low correlation coefficient of 0.33 and 0.31 for social contact. Eleven (65%) papers had weak correlations (< 0.70) between items and other scales, thus conforming to item discriminant validity. However, there was a high inter-scale correlation (> 0.70) for items of trouble with social eating, [15, 18, 23] problems with speech [8, 15], problems with swallowing [8, 21, 23, 26] trouble with social contact [26], and pain [26].
Discussion
HNC and its subsequent management have a definitive effect on the patient’s QoL incorporating their physical, psychological, social, emotional, and overall well-being. Hence, QoL assessments play a vital role in oncology practice. The information related to QoL assessments is subjective and is collected from the patients rather than from physicians. EORTC QLQ- H&N35 is a site-specific questionnaire used commonly in conjunction with its core questionnaire EORTC QLQ-C30 to assess QoL in HNC patients. EORTC QLQ-H&N35 questionnaire had been validated in different languages across the world. The present review was conducted to identify what languages, it had been validated and what were psychometric characteristics in the various languages.
After considering all eligibility criteria, a total of 17 papers were included and were reviewed. EORTC QLQ-H&N35 questionnaire had been used in 28 countries, and 21 languages to date indicate broad cross-cultural acceptance. Interestingly, the EORTC QLQ-H&N35 questionnaire had been translated into 73 different languages to date [9]. Hence, 52 linguistic translations are being underutilized. This may be because publications have not been done in those languages. More studies need to be conducted and published using these translations across the world. Most publications were from European and Asian countries. Studies conducted in America [2, 27, 28] relatively have used EORTC QLQ-H&N35. This might be explained by the fact that, traditionally, studies conducted in America make more use of other questionnaires such as the Functional Assessment of Cancer Therapy–Head Neck scale, the University of Washington Quality of Life Questionnaire or the Performance Status Scales–Head and Neck cancer this is also confirmed different reviews [29–31].
The psychometric properties of questionnaires are expressed as reliability (internal consistency) and construct validity. Assessment of reliability consists of determining that the measurement scale is reproducible and has a consistent result. Cronbach’s α coefficient is used to assess the scale reliability. Cronbach’s α coefficient ≥ 0.70 is regarded as acceptable for psychometric scales [32]. A low value of α coefficient suggests that some items either have very high variability or that items are not all measuring the same thing. Overall, there was a satisfactory performance of all scales having Cronbach’α coefficient ≥ 0.70 with an exception for speech and senses problems and less sexuality. The speech scale's poor performance might be related to the patients having cancer of the larynx and undergone a total laryngectomy. Patients might have answered positively to the two items of the scale measuring trouble talking, but not so to the "have you been hoarse' item. The contrast between these scales results can be justified because probably patients with electro-larynx and/or esophageal speech are not considering hoarseness themselves [16, 22]. The solution to this is to have an alternative to the "hoarseness" question based on the patient's perception of his or her laryngeal voice [21]. The poor performance of the scale of the senses was also in conjunction with the former scale, as the normal breathing through the nose or mouth is compromised in patients undergoing laryngectomies which further leads to a problem in senses of smell [16]. There is a possibility of a higher proportion of missing values for the sexuality items resulting in a low score on these scales [33, 34]. The possible reason for the patients wasn’t answering these questions might be because the patients were sexually inactive due to the current illness and its treatment.
Construct validity examines the items' theoretical relationship to each other and the scales and indicates how an instrument can capture what is intended to measure. Convergent and discriminant validity together used to assess construct validity. The relation between a question/item and its scale is represented by convergent validity. For this validity, a moderately high correlation (≥ 0.40) should have been found with its self-scale, as recommended [35]. On the other hand, the relation between an item and items of other scales is measured by discriminant validity. A higher value of correlation coefficient (≥ 0.70) demonstrates that these two scales have similar or likely similar constructs [36]. Overall, the scales performed very well as there was moderate to high correlation, suggesting the high convergent validity. A high correlation (> 0.70) was found in studies, in trouble with social eating [14, 15, 21], problems with speech [15, 16], problems with swallowing [8, 21, 23, 26], trouble with social contact [26], and pain [26], indicating the overlapping of a construct. It is not easy to distinguish some of these theoretically highly correlated scales. To overcome this, factor analysis (principal component) using rotational technique is recommended to check whether different scales can be placed in a similar construct or not. The factor analysis will aid in improving the reliability and validity of the questionnaire in the field of clinical oncology. One such findings of factor analysis performed by Parkar S et al. [20] showed all components associated with items related to trouble in social eating and one item of a problem in swallowing solid food were loaded in one factor; similarly, items related to pain in the throat, hoarseness of voice, cough, and the problem with swallowing were packed together in another factor.
Conclusion
Many investigators use the EORTC QLQ-H&N35 questionnaire across the world. Problems of poor performance, especially for speech, the senses, swallowing, social eating, pain, and fewer sexuality scales, need to be rectified by exchanging with appropriate items. These scales are clinically and psychometrically relevant and hence to be maintained despite their poor performance. Overall, this review provides comprehensive information on developing a psychometrically sound questionnaire that the patients and the clinicians can further accept. Also, this review could be useful in gathering data of all studies conducted worldwide so that it is possible to compare cross-cultural and psychometric properties on a single platform. EORTC QLQ-H&N35 questionnaire is a robust instrument and can be recommended to implement in oncological practice to assess HNC patients' quality of life.
Acknowledgements
Not applicable.
Author contributions
Sujal Parkar has contributed in the study conception, design of the work, data acquisition and data interpretation, revision of the work, and final approval of the version. Abhishek Sharma has contributed in the data acquisition and interpretation, revision of the work, and final approval of the version for publication.
Funding
There is no source for funding of this study as this study was self funded.
Availability of Data and Material
The datasets used and/or analysed during the current study are available from the corresponding author on reasonable request.
Code Availability
Not applicable.
Declarations
Conflict of interest
The authors declare that they have no conflict of interest.
Ethical Approval
No ethical approval is required.
Consent to Participate
Not applicable.
Consent for Publication
Authors gives consent the submission of manuscript to the journal.
Human Participants and Animals
No.
Informed Consent
Not applicable.
Footnotes
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Associated Data
This section collects any data citations, data availability statements, or supplementary materials included in this article.
Data Availability Statement
The datasets used and/or analysed during the current study are available from the corresponding author on reasonable request.
Not applicable.