Three Instruments to Assess Fatigue in Children with Cancer

Vol. 25 No. 4 April 2003

Journal of Pain and Symptom Management

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Original Article

Three Instruments to Assess Fatigue in Children with Cancer: The Child, Parent and Staff Perspectives Marilyn J. Hockenberry, PhD, RN-CS, PNP, FAAN, Pamela S. Hinds PhD, RN-CS, Patrick Barrera, BS, Rosalind Bryant, MSN, RN-CS, PNP, Jeanette Adams-McNeill, PhD, RN, Casey Hooke, RN, MSN, CPON, Christina Rasco-Baggott, RN-CS, MN, PNP, CPON, Katherine Patterson-Kelly, RN, MN, Jamie S. Gattuso, RN, MSN, CPON, and Brigitte Manteuffel, PhD Texas Children’s Cancer Center (M.J.H., P.B., R.B.), Baylor College of Medicine, Houston, Texas; St. Jude Children’s Research Hospital (P.S.H., J.S.G.), Memphis, Tennessee; University of Texas at Houston (J.A.-M.), Houston, Texas; Children’s Health Care (C.H.), Minneapolis, Minnesota; HopeLab Foundation (C.R.-B.), Stanford, California; Children’s Hospital at the University of Missouri (K.P.-K.), Columbia, Missouri; and ORC Macro (B.M.), Atlanta, Georgia, USA

Abstract The purpose of this study was to develop and test three instruments to measure fatigue in children with cancer from the perspectives of the child, parents and staff. The study consisted of three phases: instrument development, content validation, and estimations of psychometric properties of the three fatigue instruments. One hundred forty-nine children between the ages of 7–12 years presently receiving chemotherapy for cancer, 147 parents and 124 staff participated in this study. The instruments demonstrated strong initial validity and reliability estimates. This study is the first to provide valid and reliable instruments to measure fatigue in children with cancer. J Pain Symptom Manage 2003;25:319–328. © 2003 U.S. Cancer Pain Relief Committee. Published by Elsevier. All rights reserved. Key Words Children with cancer, fatigue, instruments, reliability and validity

Introduction Fatigue, a symptom commonly found in adult cancer patients, has, until recently, received limited clinical attention in pediatric oncology. In adults with cancer, fatigue is reported to be one of the most pervasive symptoms experienced

Address reprint requests to: Marilyn J. Hockenberry, PhD, RN-CS, Texas Children’s Hospital, 6621 Fannin Street, Houston, TX 77060, USA. Accepted for publication: June 25, 2002. © 2003 U.S. Cancer Pain Relief Committee Published by Elsevier. All rights reserved.

during treatment.1–6 Numerous researchers have reported that the prevalence of significant fatigue in adult patients is greater than 50% during chemotherapy,7–8 radiation therapy9–13 or with advanced cancer.14,15 In adult studies, fatigue has been shown to be a multidimensional symptom, including physical, psychological and emotional aspects.16–18 In two longitudinal studies in which pediatric oncology patients rated 10 treatment-related symptoms for symptom distress, fatigue was rated as most distressing,19,20 indicating that fatigue is a clinical problem for children and adolescents during treatment for 0885-3924/03/$–see front matter doi:10.1016/S0885-3924(02)00680-2

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cancer. More recently, adolescent and young women who are survivors of Hodgkin’s disease identified fatigue to be the most troubling sensation for them and to be what prevents them from feeling “normal.”21 Although this early work on fatigue identified it to be a troubling symptom for pediatric oncology patients and survivors of childhood cancer, fatigue remained undefined. Fatigue in children with cancer was first conceptually described in pediatric oncology patients in a study that included separate focus groups of 7–12-year-old children, 13–18-yearold adolescents, their parents, and nursing staff who cared for them.22,23 In this patient population, fatigue was defined by the children as a profound sense of being physically tired, or having difficulty with body movement such as using their arms and legs, or opening their eyes. Adolescents discussed fatigue as a changing state of exhaustion that could include physical, mental and “emotional tiredness.” Parents described their ill child’s fatigue as a state of diminished to complete loss of energy that is influenced by multiple factors including disease, nutrition, emotions, behavior, family activities, and treatment.24 Pediatric oncology staff members described patient fatigue as a symptom that is accompanied by emotional or mental withdrawal, mood changes such as irritability and decreased cooperation, and a physical desire to rest or lie down.25 Patient, parent, and staff identified causes of patient fatigue to include environmental (i.e., hospital noise, sleep disturbances), personal/ behavioral (i.e., worry, boredom), cultural/ family (i.e., expectations, activities), and treatment-related (i.e., certain medications) factors that can result in difficulties in play or social interactions, ability to concentrate, and in negative emotions.23,26 Findings from the qualitative study confirmed the presence of fatigue in children with cancer and the need for further evaluation, including measurement, of the severity of the fatigue. Only one other study was found in the literature that addressed fatigue as a symptom in children with cancer. The study evaluated the adaptation of an adult symptom assessment scale for use with children with cancer. While the scale was designed to measure a broad array of symptoms, results of this study revealed that lack of energy was the most common symptom reported.27

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The lack of reliable and valid measures to evaluate fatigue (presence, intensity, and characteristics) in children makes it difficult for clinicians to accurately recognize and interpret the intensity of the problem. Our study findings indicated that an instrument designed to assess fatigue in pediatric oncology patients should have certain characteristics: involve selfratings because fatigue is a subjective symptom; be brief and simple because young patients suffering from fatigue will be completing it; and be multidimensional because children’s own reports indicated that fatigue included physical, emotional, and mental aspects.22 In addition, parent and staff interpretations need to be documented because they define fatigue somewhat differently than children with cancer and because they identify causative factors of patients’ fatigue that are similar and dissimilar to those identified by their ill child. Parent and staff reports could validate the child’s perception of the symptom to a certain extent as well as provide an expanded view of how a child presented with fatigue and how a child responded to attempts to diminish fatigue. Children with chronic illnesses such as cancer are at risk for depression. In addition, the adult oncology fatigue literature addresses the importance of evaluating the presence of depression in cancer patients experiencing fatigue.13,16,17 Depression and fatigue can present with similar characteristics. Our study used a standardized depression instrument to help establish fatigue as a separate symptom from depression in this group of children with cancer. The purpose of this study was to develop and test three instruments to measure fatigue in pediatric oncology patients from the child, parent, and staff perspectives. Internal consistency (using Chronbach’s alpha), content validity using an expert panel approach, construct validity (exploratory factor analysis; correlational analysis among the patient, parent, and staff reports) and convergent validity (correlational analyses with items from a standardized child depression inventory) were all estimated.

Methods This instrumentation study consisted of three phases: instrument development, content validation, and estimations of psychometric properties of the three fatigue instruments. The

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instrument development phase included creating questions from the data collected during the original focus groups held with children, parents and staff. The childhood cancer fatigue model that evolved from the initial focus groups was used as the foundation for the development of the specific instrument items.22 Patients, parents, and staff from seven childhood cancer centers throughout the United States participated in the study. Eligible families whose child was being seen for an outpatient clinic visit or being admitted for scheduled chemotherapy were identified on a daily basis and were sequentially approached by one of the researchers to determine interest in participating in the study. Written parental consent and child verbal assent were obtained. The patient version of the fatigue instrument was read to the child by the researcher and parents and staff completed the questionnaire on their own. The nurse identified by the parent and child as the person most familiar with the child was the individual asked to complete the staff report instrument.

Subjects Participants included 149 English-speaking cancer patients (mean age  9.3 years, SD  1.75; range, 7–12 years), 147 parents, and 124 staff (nurses). Diagnoses of participating patients included leukemia (n  95, 64%), lymphoma (n  15, 10%), and solid tumors (n  39, 26%). In addition, these patients had no major known developmental delays and were currently receiving front-line treatment for cancer or therapy for a recurrence of disease while on treatment. Fifty-one percent of the children were within the first 6 months of diagnosis, seventy-one percent of the children were within one year from diagnosis and 97% were within three years from diagnosis. The ethnicity of the 83 males and 66 females included 104 (71%) who were Caucasian, 18 (12%) African-American, 20 (14%) Hispanic and 5 (3%) who were Asian or other. Eighteen (12%) of the children had experienced a relapse. Only those who completed instruments that had no missing responses were included in the analysis.

Instrument Development Items were derived from the focus group interview data of the previously completed qualitative study and were purposely selected to reflect

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the conceptual model developed from that qualitative study.22 The items were then formally reviewed by six experienced pediatric oncology clinicians for content validity and clarity of wording. A two-stage process (developmentquantification) for determining and quantifying content validity as specified by Lynn28 was used. The ratings from the clinicians indicated that all items achieved the needed ratings for inclusion in the final version of the instrument. Next, the three instruments were pilot tested in a group of nine children in treatment for cancer, their parents, and their health care providers. Two items were revised following the pilot testing and the directions for the child version were altered slightly. The Childhood Fatigue Scale (CFS) is a 14-item, two-part instrument. The items ask the child for a “yes” or “no” (frequency) response regarding their experience of any fatigue-related symptoms during the past week. If the statement is true for the child, he or she is asked to rate how much the problem bothers the child on a five-point Likert scale ranging from “Not at all” to “A lot.” (intensity) (Table 1). If the child has not experienced the particular problem, and has answered with a “no” response for the question, the score is zero for that question. Frequency scores range from 0 to 14, and intensity scores, also considered total fatigue scores, range from 0 to 70. Higher scores correspond to greater amounts of experienced fatigue. In this population of children, the mean intensity score was 14.0 (range: 0–55; SD 11.64) and mean frequency score was 5.6 (range: 0–14; SD 3.04) (Table 2). The five most frequent responses to the CFS are found in Table 3. Seven additional questions on Part II of the CFS ask the child to determine possible causes of their fatigue experienced during the past week (total frequency range from 0–7). Six possible causes that were verbalized by children participating in the focus groups from the original qualitative study were listed as predetermined options that included treatment, low blood counts, pain, procedures, problems with sleeping and staying overnight in the hospital. One last open-ended question was asked, “Is there anything else that causes you to be tired.” These questions were used to further assess construct validity of the CFS and PFS. The Parent Fatigue Scale (PFS) consists of 18 items regarding parents’ perceptions of the

Yes Yes

2. My body has felt different.

3. I have been tired in the morning.

No

No

No

3. The child does not have the will or desire to participate in care efforts.

Not at all 1 Not at all 1

2. The child is not well rested after a nap or a night’s sleep.

Almost never 2 Almost never 2 Almost never 2

A little 2 A little 2 A little 2

Not at all 1

Not at all 1 Not at all 1 Not at all 1

Not at all 1 Not at all 1 Not at all 1

Sometimes 2 Sometimes 2

Sometimes 2

Sometimes 3 Sometimes 3 Sometimes 3

Some 3 Some 3 Some 3

Frequently 3 Frequently 3

Frequently 3

Almost always 4 Almost always 4 Almost always 4

Quite a bit 4 Quite a bit 4 Quite a bit 4

How Much Does It Bother You

Intensity

Almost always 4 Almost always 4

Almost always 4

Always 5 Always 5 Always 5

A lot 5 A lot 5 A lot 5

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1. The child is able to participate in daily care activities at the same level of effort or for as long as usual.

Please rate the following items regarding (Insert patient’s name) behavior and mood during the past week by circling one number for each item.

Staff Fatigue Scale:

3. My child has been too tired to eat.

2. My child has had a hard time getting out of bed.

1. My child has been tired in the morning.

Please indicate how the questions reflect your child’s behaviors during the past week using the scale on the right from 1 to 5.

Parent Fatigue Scale:

Yes

1. I have been tired.

Child Fatigue Scale How have you been feeling during the past week?

Frequency

Table 1 Sample Items from the Child, Parent and Staff Fatigue Scales

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Table 2 Means, Ranges and Standard Deviations of Child Fatigue Scale, Parent Fatigue Scale and Staff Fatigue Scale Instrument

Mean

Total Child Fatigue Scalea Fatigue frequency Fatigue intensitya Factor 1 Lack of energy Factor 2 Not able to function Factor 3 Altered mood Total Parent Fatigue Scale

41

Factor 1 Lack of energy Factor 2 Not able to function Factor 3 Altered Sleep Factor 4 Altered Mood Staff Fatigue Scale a The

SD

Range

14 5.6 14

11.64 3.04 11.64

0–55 0–14 0–55

7.2

6.18

0–28

4.6

5.52

0–20

2.2

3.3

0–15

10.39

20–65

12.9

4.3

6–25

9.5

3.1

4–20

8.7

2.8

4–16

7.4

2.4

3–15

14.75

4.8

9–27

fatigue intensity score and total fatigue scale score are the

same.

amount of fatigue experienced by their child in the past week. The items are rated on a fivepoint Likert scale ranging from 1  “Not at all” to 5  “Always” (Table 1). Scores on the parent scale range from 18–90 with a higher score corresponding to greater amounts of perceived fatigue. The mean score for the 18 item PFS was 41 (range 20–65, SD 10.39). Parents also completed Part II of the PFS that consisted of 18 additional questions that evaluated possible causes of their child’s fatigue experienced during the past week. These predetermined options included items such as waking up with nightmares, not sleeping in his/her own bed, treatment, low blood counts, infection, and poor appetite. A five-point Likert scale was used to rate each cause by intensity, ranging from 1 to 5 for each cause (total range 18–90). In this population of parents,

Table 3 Most Frequent Responses to Child Fatigue Scale Item

%

n

I have not been able to play. I have been tired in the morning. I have slept more at night. I have not been able to run. I have been laying around.

75 71 58 54 54

112 105 87 81 80

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the mean for the perceived number of causes of fatigue and their intensity was 39 (range: 19–62; SD 10). The Staff Fatigue Scale (SFS) consists of nine items regarding the staff’s perception of the child’s fatigue during the past week. The staff were asked to rate the child’s fatigue based on the child’s history of their ability to perform their usual level of activities during the past week. Items are rated on a four-point Likert scale (Table 1). Scores can range from 9 to 36. In this study, the mean score on the SFS was 14.8 (range: 9–27; SD 4.79). The Depression Self Rating Scale (DSRS) is an established, 18-item instrument designed to measure the extent and severity of depression in children.29 Items are rated on a three-point Likert scale, and scores can range from 0 to 36. The DSRS was used in this study to evaluate convergent validity of the child fatigue instrument because of the importance of establishing fatigue as a separate symptom from depression. The DSRS has established reliability and validity in other child populations, including well children in elementary schools, children admitted to psychiatric facilities, and children being evaluated in outpatient psychiatric clinics. Previous testing of the DSRS included both genders, children who were white, black, or Hispanic, and children from diverse economic backgrounds.29,30 Scores of 13 and higher are considered to be indicative of depression. In our study, the mean score for the DSRS was 7.3 (range 0–24, SD 4.24). The internal consistency reliability of the DSRS using Cronbach’s alpha was 0.72.

Psychometric Testing Reliability. The internal consistency estimate for the intensity scale of the CFS was 0.84 (Cronbach’s alpha); item to total correlations for the CFS intensity score ranged from 0.34 to 0.60. Internal consistency reliability testing for the frequency scale of the CFS yielded a KuderRichardson value of 0.73. Item to total correlations for the CFS dichotomous frequency score ranged from 0.17 to 0.45. Part II of the CFS, used to examine possible causes of fatigue, had an internal consistency reliability value of 0.56 (Kuder-Richardson). The internal consistency estimate for the PFS was 0.88; item to total correlations ranged

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Table 4 Factor Loading Pattern of the Childhood Cancer Fatigue Scale (CFS) Factor Item Number and Content

1

2

3

1—tired 4—needed a nap 9—stop and rest 3—tired in the morning 6—playing around 2—body felt different 12—hard to keep eyes open 11—able to run 10—able to do activities 5—able to play 13—slept more at night 8—mad 14—trouble thinking 7—sad

0.776 0.762 0.752 0.557 0.549 0.477 0.382 0.069 0.025 0.056 0.198 0.118 0.042 0.087

0.089 0.121 0.084 0.006 0.191 0.209 0.157 0.864 0.833 0.832 0.604 0.008 0.077 0.043

0.033 0.006 0.120 0.042 0.126 0.385 0.059 0.141 0.018 0.027 0.053 0.869 0.728 0.714

1 1.000 — —

2 0.343 1.000 —

3 0.396 0.145 1.000

Correlation Matrix Factor 1 2 3

from 0.32 to 0.69. One item, ”My child has been able to complete school work”, was frequently rated as ‘not applicable’ by parents because their child was not in school at all or was experiencing frequent school absences. As a result, this item was deleted from the PFS and from further data analysis. The recalculated internal consistency of the 17-item PFS was 0.88 and item to total correlations ranged from 0.34 to 0.69. The mean intensity score of the 17 item PFS was 41 (SD  10.39). Part II of the PFS examining possible causes of the child’s fatigue yielded an internal consistency reliability value of 0.87 (Cronbach’s alpha). The internal consistency estimate of the SFS was 0.86 (Cronbach’s alpha), and item to total correlations ranged from 0.47 to 0.70.

Validity. Exploratory factor analysis using a principle components extraction and an oblique rotation (direct oblimin) was used to determine the factor structures of the three fatigue instruments. Three factors emerged for the CFS after seven iterations and accounted for 55% of the total variance explained; an eigenvalue cutoff of 1.0 was used. These factors are: lack of energy, not able to function, and altered mood. Examples of items loading on the first factor, lack of energy, included feelings of tiredness, needing rest, and feeling different. Example items on the second factor,

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not able to function, include not being able to run or play. The third factor, altered mood, included items about feeling mad or sad, and having trouble thinking. Means, ranges and standard deviations of the three CFS subscales are found in Table 2; factor loading patterns for the three subscales are found in Table 4. Four factors emerged from the PFS after 22 iterations and accounted for 58% of the total explained variance; an eigenvalue cutoff of 1.0 was used. These factors are: lack of energy, not able to function, altered sleep, and altered mood. Items loading on the lack of energy factor included perceptions of the child’s tiredness and needing rest. Examples of items loading on the second factor, not able to function, included the child’s ability to interact with others and being able to play. The third factor, altered sleep, had items such as changing sleep patterns and level of restfulness after a night’s sleep. Items loading on the altered mood factor included the child being uncooperative or irritable. Factor loading patterns for the four subscales of the PFS are found in Table 5. The nine questions on the SFS loaded onto one factor, lack of energy, explaining 48% of the total variance. Construct validity was further confirmed evaluating the correlations among the three instruments. Statistically significant correlations among the child, parent and staff fatigue instruments were noted with the strongest associations occurring between the child and parent fatigue scores (Table 6). Convergent validity was evaluated by assessing the relationship between the CFS and the Depression Self-Rating Scale (DSRS) at the total scale (r  0.561, P  0.000), and at the subscale level. All of the CFS factors were significantly correlated with the DSRS: Factor 1. lack of energy (r  0.537, P  0.000); Factor 2, not able to function (r  0.304, P  0.000); and Factor 3. altered mood (r  0.469, P  0.000). The strongest correlations (0.32) were with 5 of 7 questions on Factor 1 and all of the questions on Factor 3. The weakest correlations (0.28) were with all items on Factor 2 which describe changes in activities. Fifteen children with leukemia completed the CFS immediately before and at the conclusion of the re-induction phase of therapy. These two points in time were anticipated to represent low and high fatigue levels related to the intense treatment delivered during that phase of therapy. The interval between the two

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Table 5 Factor Loading Pattern of the Patient Fatigue Scale (PFS) Factor Item Number and Content

1

2

3

4

6—needed a nap 5—tired in the afternoon 7—no energy 3—too tired to eat 10—wanted to lie down 12—been more quiet 13—less interactive 9—play changes 15—mood changes 8—tired after night’s sleep 1—tired in the morning 4—not slept through night 2—hard getting out of bed 16—uncooperative 17—dark circles under eyes 14—more irritable 11—needed rest when walking

0.813 0.804 0.679 0.668 0.542 0.468 0.194 0.024 0.004 0.148 0.233 0.005 0.164 0.107 0.093 0.088 0.288

0.067 0.066 0.243 0.029 0.264 0.420 0.744 0.541 0.534 0.252 0.195 0.092 0.034 0.059 0.232 0.355 0.095

0.100 0.034 0.100 0.162 0.079 0.045 0.058 0.419 0.092 0.768 0.657 0.651 0.579 0.060 0.118 0.031 0.268

0.003 0.079 0.007 0.106 0.110 0.082 0.038 0.037 0.383 0.049 0.125 0.007 0.132 0.917 0.599 0.592 0.436

Correlation Matrix Factor 1 2 3 4

1 1.000 0.249 0.387 0.389

2 0.249 1.000 0.216 0.151

3 0.387 0.216 1.000 0.296

4 0.389 0.151 0.296 1.000

time periods averaged 6 weeks. A paired t-test was used to assess the ability of the CFS to detect change over time in frequency and intensity of fatigue. A statistically significant difference in frequency of fatigue (t(14)  2.686, P  0.018) was observed and a trend towards a difference in fatigue intensity was also noted (t(14)  1.967, P  0.069). The seven questions on Part II of the CFS regarding patient perceptions of possible causes of their fatigue during the past week were used to further assess construct validity of the CFS and PFS. In this population of children, the mean number of causes reported was 2.1 (range: 0–7; SD 1.66). The number of causes of fatigue significantly correlated with the frequency (r  0.667, P  0.000) and intensity (r  0.582, P  0.000) of the fatigue scores on the CFS. Thus, the more causes of fatigue identified by the child, the higher the frequency and intensity of the child’s fatigue. The most common causes of fatigue identified by the children were chemotherapy treatment and low blood counts. Parents also completed Part II on the PFS regarding their perceptions of the causes of their child’s fatigue during the past week using a 5-point Likert scale to rate the intensity of each

cause. In this population of parents, the mean for the perceived number of causes of fatigue and their intensity was 39 (range: 19–62; SD 10). An increased number of causes of fatigue correlated positively with the parent’s perception of the child’s fatigue (r  0.600, P  0.000). The most common causes of the child’s fatigue perceived by parents were chemotherapy, staying up late at night, interacting with others, low blood counts and boredom. Analysis of the demographic characteristics of this population revealed no significant differences in the frequency or intensity of fatigue based on diagnosis or age. Females indicated more frequency of fatigue compared to males (t(145)  1.994, P  0.05), but not a greater intensity of fatigue. Children experiencing a relapse indicated more intensity of fatigue (t(135)  2.137, P  0.03) but no difference in the frequency of fatigue. Children with an absolute neutrophil count less than 1,000 indicated increased frequency (t(135)  3.036, P 0.003) and increased intensity of fatigue (t(143)  2.157, P  0.03). Thirty percent (n  44) of these children had hemoglobin levels 10g/dl (range 6–14 g/dl). No differences were found in fatigue intensity or frequency based on hemoglobin level.

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Table 6 Correlations among the CFS, PFS, SFS and Depression Scale

Depression scale CFS PFS

CFS

PFS

SFS

0.56a

0.45a

0.25b 0.16c 0.43a

0.35a

aP

0.000. 0.003. c P 0.05. bP

Discussion The Childhood Fatigue Scale (CFS), Parent Fatigue Scale (PFS), and the Staff Fatigue Scale (SFS) are the first to be specifically developed for use with children receiving treatment for cancer. Strengths of these instruments are their qualitative development from actual experiences of children. In this study, the scales were completed by the participants in 10 minutes or less, even with reading the questions to the children in the study. In addition, only rarely did a child ask for item clarification. Missing data was minimal and primarily related to the item on the PFS regarding school attendance. These field observations indicate the CFS, PFS, and SFS do not place heavy burdens on children, parents, or staff members in terms of time or effort to complete the fatigue instruments. The instruments are specifically designed to reflect the nature of cancer-related fatigue and to assess the multidimensional aspects of fatigue. The findings from this study support those from the previous qualitative research as both sets of findings indicate that children receiving treatment for cancer experience fatigue and perceive treatment to be the primary cause of their fatigue. The most frequently endorsed items by children in this study included: I have not been able to play; I have been tired in the morning; I have (not) slept more at night; I have been laying around; and I had to stop and rest when walking. These questions reflect the intense lack of energy and alterations in activities of daily living experienced by some children with cancer, particularly those who are receiving treatment for a recurrence of cancer and/or those with treatment-related reduced absolute neutrophil counts. It is important to note that the children in this study were those receiving outpatient treatment; it is likely that children who are hospitalized to receive

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treatment may experience higher frequency and intensity of fatigue. Certain similarities between these findings and those observed in adults with cancer exist, including the diminished energy level, a need to slow down, an intense sense of tiredness, and an increased need for sleep.2,31–33 Physical fatigue has been shown to be an independent predictor of quality of life in adults with cancer.34,35 Collins and colleagues27 found lack of energy as the most common symptom associated with childhood cancer. Analysis of the CFS suggested that fatigue is conceptualized as three subjective dimensions: lack of energy, not able to function and altered mood. Strong correlations among these three subscales exist. Previous adult cancer fatigue instruments have had similar multidimensional components that encompass the physical, affective and cognitive aspects of fatigue.4,17,31,36 Two of the CFS factors reflect changes in physical endurance or activities of daily living. While emotional changes played a role in fatigue, less awareness of cognitive changes were noted in these younger children. This finding is consistent with child development theory that defines the 7–12 year-old child as being focused on the physical tasks and activities that they can carry through to completion rather than on cognitive associated functioning.37 In addition, findings from the factor analysis of the CFS and PFS indicate that parents are more aware of sleep alterations than are the patients themselves. A child’s perception of fatigue at this age is more focused on physical sensations and activity changes, rather than on the affective or cognitive aspects related to fatigue. Validity examination revealed significant correlations between the total instrument scores of the CFS and DSRS and among the three factor subscales of the CFS and the DSRS. Scores of the DSRS indicate that depression is rare in this patient population. However, a potentially important distinction in these correlations may imply discrimination between certain CFS and DSRS items. Higher correlations occurred between items regarding lack of energy and altered mood while lower correlations were found between items related to ability to function. For these children, changes in mood and energy level were more closely associated with depressive symptoms than changes in daily ac-

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tivities. Thus, the ‘not able to function’ subscale may be the most sensitive indicator of fatigue in children when trying to determine the differences between depression and fatigue. Test-retest reliability findings in a group of children with leukemia who were in the reinduction phase of treatment demonstrated that the CFS can detect changes in fatigue frequency; a trend toward significant changes in fatigue intensity was observed but the ability of the CFS to detect change in intensity needs to be further assessed in a larger patient sample. Further support for the ability of the CFS to detect change was found in the subset of children being treated for a relapse as that group reported both increased frequency and intensity of fatigue in comparison to children who had not experienced a relapse. This finding supports the sensitivity of the instrument to detect changes in fatigue in children who are receiving different types of chemotherapy treatment. An additional finding to support the sensitivity of the instrument is that children with lower white blood cell counts had more intensity and frequency of fatigue; this occurred at a time when the child was more susceptible to illness. Both children and parents identified low blood counts as a common cause of fatigue. It is too early (based on this initial instrument study) to propose cutoff scores for the CFS, PFS and SFS instrument scores regarding the presence or intensity of fatigue in children receiving chemotherapy for cancer that merits a fatigue intervention. Additional studies are needed on children off therapy and children without cancer to determine how fatigue is experienced in children in general. At this early stage in scale development, it would appear that values greater than the means of the scales may be further investigated as indicators of clinically significant fatigue. Findings from this study suggest that a score above the means for the child fatigue frequency (mean 5.6) and intensity (mean 14) support the presence of fatigue in children. The wide range in total scores for the CFS suggest further evaluation is needed in a different patient population, perhaps those hospitalized for a particular point in their treatment plan. In addition the low levels of reported fatigue in these children reflected by the intensity scores reveals that although fatigue is present, these children may not be bothered by it. Other child self-reports

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that measure symptoms also have found lower reporting of symptoms by children when compared to parents and caregivers.38 The PFS had a mean of 41 for this population and this value could be examined in the future as the indicative cutoff score for fatigue perceived by parents. The SFS had a mean of 14.8 and that score could be similarly used for future evaluation. Future studies are needed to determine further sensitivity of the instruments in evaluating fatigue experienced by children with different types of cancer, receiving various intensities of treatment during different phases of therapy. This study is the first to provide valid and reliable instruments to measure fatigue in children with cancer. The instruments have been designed to be brief, valid and feasible for assessing the multidimensional aspects of fatigue in this population. These new instruments will pave the way for a better conceptual understanding of the epidemiology of fatigue and provide evaluation of much needed interventions for this symptom in the future.

References 1. Cella D, Davis K, Breitbart W, et al. Cancerrelated fatigue: prevalence of proposed diagnostic criteria in a United States sample of cancer survivors. J Clin Oncol 2001;19(14):3385–3391. 2. Curt GA. Fatigue in cancer. BMJ 2001;322(7302): 1560. 3. Portenoy RK, Itri LM. Cancer-related fatigue: guidelines for evaluation and management. Oncologist 1999;4:1–10. 4. Curt GA, Breitbart W, Cella D, et al. Impact of cancer-related fatigue on the lives of patients: new findings from the Fatigue Coalition. Oncologist 2000;5:353–360. 5. Okuyama T, Akechi T, Kugaya, et al. Development and validation of the cancer fatigue scale: a brief, three-dimensional, self-rating scale for assessment of fatigue in cancer patients. J Pain Symptom Manage 2000;19(1):5–14. 6. Portenoy RK. Cancer-related fatigue: an immense problem. Oncologist 2000;5:350–352. 7. Alison R, Ream EM, Wilson-Barnett J. Fatigue in patients receiving chemotherapy: patterns of change. Cancer Nurs 1998;21(1):17–30. 8. Stone P, Richardson A, Ream E, et al. Cancerrelated fatigue: inevitable, unimportant and untreatable? Results of a multi-centre patient survey. Ann Oncol 2000;11:971–975. 9. Smets EMA, Visser MRM, Garssen B, et al. Understanding the level of fatigue in cancer patients

328

Hockenberry et al.

undergoing radiotherapy. J Psychosom Res 1998; 45(3):277–293. 10. Smets EMA, Garssen B, Cull A, et al. Application of the Multidimensional Fatigue Inventory (MFI-20) in cancer patients receiving radiotherapy. Br J Cancer 1996;73:241–245. 11. Greenberg DB, Sawicha J, Eisenthal S, et al. Fatigue syndrome due to localized radiation. J Pain Symptom Manage 1992;7:38–45. 12. Hickok JT, Morrow GR, McDonald S, et al. Frequency and correlates of fatigue in lung cancer patients receiving radiation therapy. J Pain Symptom Manage 1996;11:370–377. 13. Viser MRM, Smets EMA. Fatigue, depression and quality of life in cancer patients: how are they related? Support Care Cancer 1998;6:101–108. 14. Krishnasamy M. Fatigue in advanced cancer— meaning before measurement? Int’l J Nurs Studies 2000;37:401–414. 15. Stone P, Hardy J, Broadley K, et al. Fatigue in advanced cancer: a prospective controlled crosssectional study. Br J Cancer 1999;79:1479–1486. 16. Akechi T, Kugaya A, Okamura H, et al. Fatigue and its associated factors in ambulatory cancer patients: a preliminary study. J Pain Symptom Manage 1999;17(1):42–48. 17. Winningham ML, Nail LM, Burke MB, et al. Fatigue and the cancer experience: the state of the knowledge. Oncol Nurs Forum 1994;21:23–36. 18. Holley SK. Evaluating patient distress from cancerrelated fatigue:an instrument development study. Oncol Nurs Forum 2000;9(27):1425–1431. 19. Hinds P, Scholes S, Gattuso JS, et al. Adaptation to illness in adolescents with cancer. J Pediatric Oncol Nurs 1990;7(2):54–55. 20. Hinds PS, Quargnenti A, Bush A, et al. An evaluation of the impact of a self-care coping intervention on psychological and clinical outcomes in adolescents with new diagnosed cancer. Euro J Oncol Nurs 2000; 4(1):6–17. 21. Crom DB, Hinds PS, Gattuso JS, et al. Perceived vulnerability among survivors of Hodgkin’s disease. In preparation of paper presented at the 25th Annual Conference of the Association of Pediatric Oncology Nurses. October 2001, Memphis, TN.

Vol. 25 No. 4 April 2003

25. Hinds PS, Hockenberry-Eaton M, Quargnenti A, et al. Fatigue in 7- to 12-year old patients with cancer from the staff perspective: an exploratory study. Oncol Nurs Forum 1999;26(1):37–45. 26. Hockenberry-Eaton M, Hinds PS. Fatigue in children and adolescents with cancer. In: Winningham ML, Barton-Burke M, eds. Fatigue in cancer. Sudbury: Jones and Bartlett Publishers, 2000:71–85. 27. Collins JJ, Byrnes ME, Dunkel IJ, et al. The measurement of symptoms in children with cancer. J Pain Symptom Manage 2000;19(5):363–-377. 28. Lynn M. Determination and quantification of content validity. In: FS Downs, ed. Handbook of research methodology: considerations in efficient research design and data analyses. New York: American Journal of Nursing Co., 1988:131–136. 29. Birleson P. The validity of depression disorders in childhood and the development of a self-rating scale: A research report. J Child Psychol and Psychiatry 1981;22:73–88. 30. Birleson P, Hudson I, Grey-Buchanan D, Wolff S. Clinical evaluation of a Self-Rating Scale for Depressive Disorder in childhood (Depression Self-Rating Scale). J Child Psychol and Psychiat 1987; 28:43–60. 31. Wu H, McSweeney M. Measurement of fatigue in people with cancer. Oncol Nurs Forum 2001;28(9): 1371–1384. 32. Berger AM, Higginbotham P. Correlates of fatigue during and following adjuvant breast cancer chemotherapy: a pilot study. Oncol Nurs Forum 2000; 27(9):1443–1448. 33. Barsevick AM, Whitmer K, Walker L. In their own words: using the common sense model to analyze patient descriptions of cancer-related fatigue. Oncol Nurs Forum 2001;28(9):1363–1369. 34. Hann DM, Garovoy N, Finkelstein B, et al. Fatigue and quality of life in breast cancer patients undergoing autologous stem cell transplantation: a longitudinal comparative study. J Pain Symptom Manage 1999;17(5):311–319. 35. Visser MRM, Smets EMA. Fatigue, depression and quality of life in cancer patients: how are they related? Support Care Cancer 1998;6:101–108.

22. Hockenberry-Eaton M, Hinds PS, Alcoser P, et al. Fatigue in children and adolescents with cancer. J Pediatric Oncol Nurs 1998;15(3):172–182.

36. Meek PM, Nail LM, Barsevick A, et al. Psychometric testing of fatigue instruments for use with cancer patients. Nurs Research 2000;49(4):181–190.

23. Hockenberry-Eaton M, Hinds P, O’Neill JB, et al. Developing a conceptual model for fatigue in children. Euro J Oncol Nurs 1999;3(1):5–11.

37. Erickson EH. Childhood and society, 2nd ed. New York: WW Norton, 1963.

24. Hinds PS, Hockenberry-Eaton M, Gilger E, et al. Comparing patient, parent, and staff descriptions of fatigue in pediatric oncology patients. Cancer Nurs 1999;22(4):277–287.

38. Achenbach, TM, Howell CT, Quay, HC, Conners CK. National survey of problems and competencies amongh four-to-sixteen-years-olds: parents’ reports for normative and clinical samples. Monogr Soc Res Child Dev 1991:56(3):1–131.