|Year : 2020 | Volume
| Issue : 3 | Page : 445-454
Construction and validation of a quality of life tool for pediatric patients of Indian origin with cancer: A single-center prospective study
Chindhu Shunmugasundaram1, Vidhubala Elangovan1, Venkatraman Radhakrishnan2
1 Department of Psycho Oncology, Cancer Institute (WIA), Chennai, Tamil Nadu, India
2 Department of Pediatric Oncology/Medical Oncology, Cancer Institute (WIA), Chennai, Tamil Nadu, India
|Date of Submission||11-May-2020|
|Date of Decision||14-Jun-2020|
|Date of Acceptance||29-Jul-2020|
|Date of Web Publication||19-Sep-2020|
School of Psychology, The University of Sydney, Level 6, Chris O'fBrien Lifehouse, Missenden Road, NSW 2050
Source of Support: None, Conflict of Interest: None
Background: Quality of life (QOL) is an important clinical end point in pediatric oncology. The lack of a culture-specific measure to assess the QOL of Indian pediatric patients with cancer has led to this study.
Objectives: This study was aimed at constructing and validating a QOL tool for Indian pediatric patients with cancer.
Materials and Methods: This was a single-center prospective study conducted at the Cancer Institute, WIA, in Chennai, India, between July and October 2013. The study was conducted in two phases. Phase I consisted of generating and drafting of items, face validity, and field and pilot testing. Phase II involved establishing the validity and reliability of the measure. A total of 264 pediatric cancer patients aged 10–17 years were included for the construction of this measure. Factorial analysis, “t” test, Spearman's product moment correlation, and Cronbach's alpha coefficient were employed for data analysis.
Results: A reliable, valid, and internally consistent measure containing 31 items named Cancer Institute Pediatric Oncology Quality of Life Questionnaire-31 (CI-Ped Onc QLQ 31) was developed to assess the QOL of pediatric patients with cancer. The Cronbach's alpha and the Guttman split-half reliability of the developed measure were 0.83 and 0.80, respectively. The four factors that emerged after factor analysis (eigenvalues ranging from 7.495 to 1.495 with 46.53% variance) were grouped into three: “physical well-being,” “psychosocial well-being,” and “treatment-related concerns.” Discriminant validity was established within the gender and treatment status.
Conclusions: The CI-Ped Onc QLQ 31 was constructed and validated. It was found to be suitable for pediatric patients of Indian origin with cancer. This measure can be used for screening by health professionals across various spectra, to plan interventions and for future research in the field.
Keywords: Patient-reported outcome measure, pediatric psycho-oncology, psychosocial oncology, quality of life, well-being
|How to cite this article:|
Shunmugasundaram C, Elangovan V, Radhakrishnan V. Construction and validation of a quality of life tool for pediatric patients of Indian origin with cancer: A single-center prospective study. Cancer Res Stat Treat 2020;3:445-54
|How to cite this URL:|
Shunmugasundaram C, Elangovan V, Radhakrishnan V. Construction and validation of a quality of life tool for pediatric patients of Indian origin with cancer: A single-center prospective study. Cancer Res Stat Treat [serial online] 2020 [cited 2021 Apr 23];3:445-54. Available from: https://www.crstonline.com/text.asp?2020/3/3/445/295536
| Introduction|| |
Two decades ago, cancer in children was considered an acute disease with high morbidity., However, the recent advancements in the treatment have changed this scenario by increasing the survival time of children with cancer. During the treatment as well as in the posttreatment phase, the normalcy and overall sense of well-being of children with cancer get disrupted. Some of the major issues faced by children with cancer include fear, low self-esteem, fatigue, depression, distress, loneliness, crying spells, anxiety, missing school, and restricted social functioning and recreational activities.,, These psychosocial issues tend to affect the quality of life (QOL) of pediatric patients with cancer; therefore, it is essential to assess QOL in these patients in addition to the evaluation of clinical end points.,,
Several standardized psychometric pediatric oncology QOL measures have been developed in countries such as the United States of America (QOL-Cancer Survivors, Pediatric Quality of Life Inventory [PedsQL] 4.0, Miami Pediatric Oncology QOL tool),,, Taiwan quality of life in childhood cancer [QOLCC]),, the Netherlands (TNO-AZL Preschool Children Quality of Life [TAPQOL]), Israel (Children's Quality of life [CHQ]), and Turkey. The major limitations of these patient-reported outcome measures (PROMs) or proxy-reported outcome measures include small sample size,, lack of cross-cultural validation, insufficient attention to the children's ability to comprehend and complete the tests, not adhering to the dimensions of QOL as stated by the World Health Organization, and not using relevant questions for testing.,
The patients' cultural backgrounds influence their perception about cancer, thus affecting their understanding, communication, disease management, and coping techniques., In Asian countries such as India, it is not very common for children to share their feelings and emotions with their parents; hence, children find it difficult to communicate their emotional needs with their parents or primary caregivers.,,,, Moreover, their needs, priorities, and perceptions vary with age. Thus, constructing an age-appropriate, culturally-sensitive PROM to assess the QOL of Indian pediatric patients with cancer can involve several challenges and limitations. Currently, there are no QOL measures that have been specifically designed for pediatric patients with cancer in India. This study is aimed at bridging the existing gap by developing a PROM to assess the QOL of pediatric patients with cancer that is relevant to patients of Indian origin across the globe.
| Materials and Methods|| |
General study details
This was a prospective study conducted at the Cancer Institute, WIA, in Chennai, India, between July and October 2013. The study was conducted in the inpatient and outpatient departments of the medical, surgical, radiation, and pediatric oncology departments of Kumaran Hospital and Cancer Institute, WIA, in Chennai, India. The study was approved by the Institutional Thesis Review Committee (ITRC/13/04) and was conducted in accordance with the Declaration of Helsinki for the ethical conduct of human research. The study was not registered with a clinical trial registry as it was not a clinical trial. No funding was obtained for this study. Written informed consent was obtained from all caregivers or parents of the participants before their participation in this study.
Literate pediatric patients with cancer aged between 10 and 17 years, irrespective of their gender, socioeconomic status, disease site, stage, treatment status, and prognosis, were recruited. The United Nations Educational, Scientific, and Cultural Organization defines literacy as “the ability to identify, understand, interpret, create, communicate, and compute, using printed and written (and visual) materials associated with varying contexts. Literacy involves a continuum of learning to enable an individual to achieve his or her goals, to develop his or her knowledge and potential, and to participate fully in the wider society.”
The primary objective of the study was to construct and validate an age- and culturally-appropriate QOL tool for pediatric patients of Indian origin with cancer.
A total of 264 participants were included in the test construction process, and the sample size varied across different phases. Purposive and convenient sampling techniques were used for the recruitment of patients. Most of the current-generation children in India learn English either as a first or second language. Both the cancer hospitals included in this study cater to patients from several southern states of the country. Therefore, the proposed PROM assessing the QOL for native Indian pediatric patients with cancer was developed in English and not in any specific regional language. Only those patients with adequate knowledge of English were included during the crucial phases of assessing the face validity and pilot testing. The subject's working knowledge of English was not assessed rigorously except for asking the patients and their parents if they knew how to read, write, or speak in English during the recruitment.
The study was conducted in two phases. In Phase I (July 2013), items were pooled and drafted, the face validity was tested, and field and pilot tests were performed with experts and patients. In Phase II (August–October 2013), factorial validity, discriminant validity, and internal consistency reliability of the measure were established.
| Item Pooling|| |
Various aspects of QOL relevant to the pediatric patients with cancer were collated from different sources such as literature (systematic search of the literature using online databases such as PsycInfo, PubMed, and Google Scholar), existing measures, and interviews conducted with patients/caregivers/oncologists. They were framed into sentences in simple English language.
| Face Validity|| |
A Delphi process was adopted to establish the face validity. As per Linstone,, the minimum panel size is 8, but this rule is not rigid, and the panel size can vary between 4 and 2000. The decision regarding the panel size is empirical and pragmatic. In this study, we had 8 experts who took part in the Delphi process, considering factors such as time and expense.
- Step one: An expert panel of nine members with an in-depth knowledge of the topic was approached based on the convenience, and responses were received from eight of them (two psycho-oncologists, three oncologists, two psychologists with research background, and one child psychologist). The framed items were given to the panel members, and they were asked for their consensus opinion on the relevance, clarity, and comprehensiveness of the PROM. They were also asked to indicate the domains to which each item belonged
- Step two: The developed PROM was administered to 15 patients fulfilling the eligibility criteria. They were asked to indicate the relevance, clarity, and comprehensiveness of all the items in relation to their disease and treatment status. A complete response was obtained from 11 out of 15 patients.
| Pilot Testing|| |
For this, 10 consecutive patients fulfilling the eligibility criteria and who were scheduled to meet their clinicians for follow-up were approached. Out of these, two patients were not interested in participating in the study. For the remaining eight, a debriefing interview was conducted, in which they were questioned about the difficulties in completing the measure, the relevance and clarity of each item, the time taken to complete the measure, their unwillingness to respond to any item, assistance with completing it, and any missing items important to them.
Standardization of the measure
| Factorial Validity|| |
After pilot testing, the developed PROM was administered to 174 participants, including both inpatients and outpatients, meeting the eligibility criteria. The sample size for this phase was estimated based on the recommendations in the literature,, suggesting 5–10 participants per item in the measure being examined. Thus, a sample size of 153 was required. However, as a larger sample size is required for factor analyses,, we considered a minimum of 170 participants.
| Discriminant Validity|| |
Discriminant validity of the PROM was established using the same sample set as that used for establishing the factorial validity.
| Reliability|| |
To establish the internal consistency reliability of the constructed measure, a total of 71 participants were included. This was because the internal consistency reliability was calculated as a preliminary analysis to ensure that the developed PROM was reliable.
| Procedure|| |
Patients and their primary caregivers were briefed about the study, and written informed consent was obtained from them. The measure was administered to those whose parents and primary caregivers consented to participate in the study. Three psycho-oncologists who could speak the native language were oriented and trained in the administration of the measure. They assisted those children who had difficulties responding (due to aches or tiredness), by either reading out the measure to them or by filling it for them. The method of administration was discussed and agreed upon to control the bias. In a country with a low literacy rate, like India, even for adult patients, PROMs are either used to screen for clinically relevant outcomes or to assess the disease severity. Therefore, it is highly likely that children (out of symptom burden or incapacity) may find it difficult to fill out forms that they are not familiar with. Thus, by following a uniform procedure for data collection, we attempted to control any possible bias.
This PROM development study was based on the classical test theory (CTT). CTT was chosen for the following reasons: (a) as this study was sample dependent, the generalization of its findings would be feasible; (b) CTT is a well-known theory that has been used for decades to assess the reliability and validity of measures; (c) CTT is a test score theory that is more applicable to this study; (d) a larger sample size of over 500 participants is not required with CTT; and (e) CTT is less time-consuming than item response theory.
The psychometric analyses of the measure were undertaken using the Statistical Package for the Social Sciences Version 20.0 (IBM Corp. Released 2012. IBM SPSS Statistics for Windows, Version 20.0. Armonk, NY: IBM Corp.) Quantitative analyses such as frequency and descriptive statistics, correlation, “t” test, and factorial analysis were used to establish the face validity, reliability, discriminant validity, and factorial validity, respectively. The principal component analysis method using the varimax rotation was used for the factor analysis. Reliability tests such as Guttman split-half reliability and Cronbach's α coefficient were conducted. The Kaiser-Meyer-Olkin (KMO) measure (significance of P < 0.001) was used for measuring the sampling adequacy.
| Results|| |
A total of 264 participants were recruited during the various phases of the study between July and October 2013. The details of patient recruitment, evaluation, and analysis are provided in [Figure 1].
Item pooling and drafting
A total of 101 generated items that were related to the various concerns of the pediatric patients with cancer were reviewed and scrutinized for repetition, overlap, and priority. Care was taken to ensure that all the relevant concerns addressing every aspect of the QOL were included [Figure 2]. Finally, 32 items were shortlisted and drafted as statements in the English language. The response anchors on a three-point Likert scale that included “not at all,” “somewhat,” and “always.”
| Step 1 (Experts' Concurrence)|| |
In the Delphi process, a total of 31 items relevant to the physical, social, psychological, cognitive, treatment-related, and school functioning-related aspects of life were identified by 8 experts. A consensus was arrived at within two rounds of the Delphi process. Experts suggested using a four-point response scale instead of a three-point scale, to increase the sensitivity and reduce the ambivalence. After step 1, 17 items were retained without change, 1 was deleted, and 14 were modified; there were 31 items at the end of face validity. [Table 1] highlights these changes.
|Table 1: Items drafted and the changes made to the items during face validity and pilot testing|
Click here to view
| Step 2 (Patients' Concurrence)|| |
Eleven participants provided a complete response to the administered PROM. The items that were agreed upon by more than 80% of the participants based on their clarity and comprehensiveness were retained [Table 2]. Only one newly diagnosed participant found a few items related to school, social, and psychological issues irrelevant. This could be because the subject had not started the treatment and may not have experienced these issues yet [Table 2].
The developed 28-item PROM was administered to 8 consented participants. Of these, many did not understand the meaning of some words, such as “frustrated,” “disrupted,” “appetite,” “nausea,” “fewer,” and “'siblings.” Three of the patients undergoing treatment mentioned that the items “I cannot do things that other kids my age do” and “I have fewer friends than before” were more of “yes” or “no” questions and felt that these were irrelevant to them at that point of time. A few new concerns arose, which were then addressed, and a few items were modified based on the suggestions [Table 1]. Items that were double loaded or vague were split into two. Items related to communication, information, and hospital anxiety were added. The mean time taken to complete the measure was 7.9 min. When it was self-administered, it took between 4 and 10 min, and when administered by a psychologist, it took between 5 and 15 min based on the child's education or comprehension level. At the end of the pilot testing, our measure had 31 items with four response anchors, “not at all,” “somewhat,” “often,” and “always.”
Standardization of the measure
Characteristics of the 174 participants included for assessing the factorial validity, discriminant validity, and reliability are presented in [Table 3].
The KMO measure of sampling adequacy suggested that the sample size was adequate to run factor analysis (KMO = 0.786). Barlett's test of sphericity was significant KMO = 2024.16, P < 0.001).
Eight factors emerged after principal component analysis with Varimax rotation, with majority of the items loading on to the first four factors. The remaining factors were loaded with items that were already loaded on to the first few factors. Therefore, the analysis was re-run restricting the number of factors to four. These four factors had eigenvalues ranging from 1.49 to 7.49 with a total variance of 46.53%, and the loading ranged from 0.31 to 0.77.
The items in factor 4 such as “I have vomiting or feel like vomiting,” “I feel tired,” “I am not able to remember things as usual,” and “I am concerned about changes in my body” were found to be more relevant to the physical aspects and loaded on to factor 1. Hence, factor 4 was removed. The second and third factors with 11 and 6 items, respectively, were retained without modification. Consequently, four factors that emerged after re-analysis were re-grouped into three factors and named “physical well-being,” “psychosocial well-being,” and “treatment-related concerns” [Table 4] and [Table 5].
|Table 5: Factor loadings and commonalities with varimax rotations based on principal component analysis for each item|
Click here to view
Scoring and interpretation
The developed measure had 31 items in total. For each item, the score ranged from “3” (not at all) to “0” (always). Twelve items were negatively framed, had negative loading, and were reverse scored. Scores were categorized into three groups based on percentiles for the ease of interpretation. The scores on the 25th and 75th percentiles were 46.75 and 66.25, respectively. Hence, scores below 47 were interpreted as “low QOL,” those between 47 and 65 as “average QOL,* and 66 and above as “high QOL.”
Discriminant validity of the measure was established considering the gender and treatment status. These two factors were taken into consideration based on studies, which indicated that there were differences in QOL based on these factors. The scores varied between the two groups based on the treatment status (t = −6.966, P = 0.001) and gender (t =0.48, P < 0.01), thus establishing the discriminant validity of the measure.
Cronbach's alpha for the measure was found to be 0.833, and the Guttman split-half coefficient of the scale was 0.803, indicating internal consistency among the items.
| Discussion|| |
A 31-item PROM to assess the QOL of pediatric patients with cancer was developed and named “Cancer Institute Pediatric Oncology Quality of Life Questionnaire-31 (CI-Ped Onc QLQ 31).” It has been validated and found to be reliable (α = 0.833) to assess the QOL of patients between the ages of 10 and 17 years. The CI-Ped Onc QLQ 31 is a multifactorial scale with three factors, namely “physical well-being,” “psychosocial well-being,” and “treatment-related concerns.” It could serve as one of the outcome measures for assessing the QOL of pediatric patients of Indian origin across the globe. With increasing numbers of Indians migrating to other countries, it is essential to have psychological measures that assess the outcomes reflecting concerns relevant to them.
Research, has shown that underlying problems such as physical and interpersonal changes impair the ability of pediatric patients with cancer to perform various activities of daily life like before. These issues were addressed in this measure. Moreover, the limitations of already existing PROM or proxy-reported outcome measures and challenges of constructing a measure for children,, were taken into consideration during the development of CI-Ped Onc QLQ 31.
Although there are many regional languages in India, English is usually the medium of instruction in most schools across the country, and it is a common language known to most. As most Indian children have adequate knowledge of English, the measure was constructed in this language. The language was kept as simple as possible taking into consideration the fact that participants were from mixed socioeconomic and linguistic backgrounds (viz., Tamil, Telugu, and Hindi). In addition to this, many participants were the first-generation learners. Adapting the measure to native Indian languages is the next step that needs to be undertaken.
Most of the existing measures are long, with many items (>40) to assess the QOL. The QOLCC and PedsQL 4 were the only measures with fewer items (<35) in line with the CI-Ped Onc QLQ-31 developed in our study. It is important to consider the number of items as children tend to have a short attention span and might lose focus with longer measures.,,,, PedsQL has questions that require children to recollect certain facts from the past months, which could make these questions difficult to answer.
Another reason that prompted the development of CI-Ped Onc QLQ 31 was the presence of parent or physician proxies in other existing measures. Proxy forms are usually filled by physicians observing the children and by parents who might judge children based on their perceptions.,,, Our QOL measure has addressed this limitation. It should be noted that the CI-Ped Onc QLQ 31 is meant for children aged above 10 years, as no proxy form was developed. Information obtained on QOL could be more reliable when answered by those who are experiencing the problem. The existing measures with proxies could be applicable to younger children.
The existing PROM or proxy-reported measures assess the crucial aspects of QOL such as physical, psychological, and social functioning. The number of factors to assess the QOL in these measures ranges from 3 to 16. The CI-Ped Onc QLQ 31 developed in our study has 3 factors and adequately evaluates all the crucial aspects of QOL in oncology.
For the pubescent population, who are neither children nor adults, the physical health reflects their overall well-being and the meaning of health changes during the different stages of life. Younger adolescents usually focus more on somatic feeling states, and older adolescents describe health as the ability to perform role functions. Compared to healthy children, those with cancer might not perform well physically. This can affect their psychological health. Usually, patients undergoing treatment tend to experience decreased familial and social ties, become unable to participate in activities due to fatigue, and experience social isolation; this can be the result of low blood counts, nausea, vomiting, and decreased immunity. Such disease- and treatment-related effects can be negative and pervasive for children with cancer.
Most of the existing measures consider the effect of the participants' age group on the QOL, except for the child health questionnaire.,,,,,,,, The validated CI-Ped Onc QLQ 31 can be administered to children aged between 10 and 17 years, an age group during which children acquire the abilities for logical structuring, grasping concepts (both concrete and abstract), and performing higher order mental operations, according to the developmental psychology.
There are situations when children feel they might burden their parents with their emotions and tend to restrict themselves from communicating their feelings.,,, The sense of weakening experienced by pediatric patients with cancer worsens when they are unable to communicate their feelings with those around them. This psychological component accumulates and tends to worsen their bodily side effects. The primary rationale for constructing this PROM was to assess and understand the QOL and the underlying psychological state of these patients. Accordingly, the factors were named “physical well-being,” “psychological well-being,” and “treatment-related concerns” and addressed the motive.
Physical well-being was the first factor that emerged with 14 items (”I have pain,” “I am allowed to play outside,” “My hunger is normal as usual,” “My sleep is not good”). This factor is in line with the physical restrictions domain of the Pediatric Oncology Quality of Life Scale, Physical Functioning Factor of QOLCC, TAPQOL, PedsQL 4.0, CHQ, and Physical Well-Being Factor of QOLCS. The items in this factor underline the concerns regarding experiencing physical symptoms as a result of treatment and those that arise as a consequence of the physical symptoms.
The second factor emerged with 11 items. The items in this factor describe psychosocial effects of cancer treatment. As the items that reflect one's feelings about missing school, friends, family, social gatherings, and functioning focus on the psychosocial element, this factor was named “psychosocial well-being.” Patients with cancer undergo significant physical and psychological changes posttreatment. Hence, in addition to their physical assessment, a psychological assessment is also necessary.,
The third factor emerged with six items and was named “treatment-related concerns” as they described the concerns that arise due to treatment. It had items related to information needs, worry about the future, and anger because of having to undergo treatment. This is in line with the dimension “treatment disease-related symptoms” of QOLCC. The relationship between being able to eat and the effects of treatment such as chemotherapy and radiation goes hand in hand. One of the major side effects of chemotherapy and radiation is vomiting, indicating that statements addressing eating and vomiting could also fall under treatment-related concerns.
Based on the statistical computation of scores for girls and boys, it was found that girls scored higher in QOL than boys; however, the fact that most of the girls (64%) who participated in this study were in the follow-up category should be taken into consideration. This could have led to higher scores, as in the study done on childhood survivors; it is also in line with the study done in Israel which reported that girls have higher QOL than boys.
The limitations of our scale include the availability of our measure only in the English language and that it is solely meant for patients aged between 10 and 17 years, without any parallel or proxy forms. Indian children raised in a foreign nation from birth might find the measures developed in that specific country or in a western country more useful. However, those who migrate in between and do not have enough exposure to a foreign curriculum may find an Indianized version of the QOL more useful and easier to answer rather than a measure developed with idioms and culture-specific terms, such as “soccer” or “rollerblading.” Further research can be conducted to make pictorial representations of the scale to reach out to pediatric patients with cancer younger than 10 years old and to adapt this measure to all regional Indian languages.
| Conclusions|| |
CI-Ped Onc QLQ 31 uses simple language, is less time-consuming, and categorizes all relevant aspects of the QOL of Indian children within three factors; moreover, it can be administered in any clinical setting.
The authors acknowledge Ms. Michelle, Mr. Shameem, Mr. Irfan, Mr. Sundar, Ms. Jisha, Ms. Gargi, and Ms. Radhika of the Department of Psycho-Oncology at Cancer Institute (WIA) for their assistance in data collection for this project. We acknowledge Ms. Subathra and Ms. Shakuntala for reviewing and editing the manuscript. We are also thankful to the experts who gave their expert comments and patients who participated in this study during the development of the tool. We acknowledge Dr. Arun Seshachalam for his initial coordination to begin the project and his assistance in pooling the items.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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[Figure 1], [Figure 2]
[Table 1], [Table 2], [Table 3], [Table 4], [Table 5]