Correlation between the Child Health Questionnaire and the International Knee Documentation Committee score in pediatric and adolescent patients with an anterior cruciate ligament tear
Robert E. Boykin, MD, Eric D. McFeely, BA, Dave Shearer, MD, Jeremy S. Frank, MD, Christopher C. Harrod, MD, Adam Y. Nasreddine, MA, Mininder S. Kocher, MD, MPH
Children’s Hospital Boston, Division of Sports Medicine
Harvard Medical School, 300 Longwood Avenue, Boston, MA 0211
Lower extremity injuries in children and adolescents are common and increasing secondary to greater training intensity and participation in competitive sports5, 16. A study in soccer players aged 5-18 years illustrated that 30.8% of all knee injury claims and 6.7% of total insurance claims were secondary to ACL injuries21. Although the true incidence and prevalence of injuries to the anterior cruciate ligament (ACL) in this population remains unknown, reports have noted an increasing frequency in the pediatric population (12,15,21).
The International Knee Documentation Committee (IKDC) Subjective Knee Evaluation Form is a knee specific (rather than disease specific) functional assessment tool which is commonly used to evaluate the outcomes of orthopaedic interventions in adult patients9-10. The IKDC contains 18 questions with a maximum score of 100 points. Its validity, reliability, responsiveness, and normative data have been established in a number of knee conditions in an adult population1, 9-10 and more recently in the pediatric population with knee disorders14. The IKDC form was correlative to physical function, but not emotional function in validation studies in adults. Normative pilot data scores in a pre-adolescent population have been reported22 and recent data have established the validity and internal consistency of the IKDC in patients aged 6-1820, however the appropriate use in pediatric and adolescent populations remains debated (1).
The Child Health Questionnaire (CHQ) is a generic health related quality of life instrument that has been validated for a wide range of pediatric conditions in a number of different languages for children age 5-1813, 17-19, 24-26. The CHQ is similar in structure and methodological approach to the Short Form – 36 (SF-36)7, with the exception that the CHQ was developed specifically for children. The questionnaire encompasses multiple aspects of physical, psychological, and social health and includes 12 domains (physical functioning, emotional role, social limitations – behavior, social limitations – physical, bodily pain, behavior, mental health, self esteem, general health, change in health, family activities, and family cohesion). The CHQ – CF87 is a self report form utilized in adolescents. It has been documented that musculoskeletal injury affects children in realms outside of sports participation and physical activity, including school attendance and performance (2,4,8,23), however the full social implications of injury in the pediatric age group are not well understood.
The intent of this study was to analyze a prospectively collected database to identify correlations between knee function and health related quality of life in pediatric and adolescent patients with an ACL tear. The primary purpose was to document correlations between domains of the IKDC and CHQ questionnaires in these patients to determine the effect of an ACL injury on physical, psychological, and social health. We hypothesized domains outside of physical function and bodily pain would be positively correlated with knee function.
Between May 2007 and February 2009 135 patients presented to our institution with an ACL tear and were enrolled in a prospective database. All patients included were age 18 or younger who had completed both the IKDC and CHQ- CF87 at the same visit. This included patients being treated operatively and non-operatively in all phases of treatment. There were no patients who completed both surveys at multiple time points; therefore, the study is cross-sectional in design.
The IKDC survey was scored using the most recent update described by the IKDC1, while the CHQ was scored as recommended by the HealthACTCHQ 6Survey scores and other pertinent data including age, gender, and treatment were extracted from the database for further analysis. The study was approved by the Institutional Review Board at our institution.
To assess the impact of knee function on quality of life, Spearman’s rank correlation coefficient was calculated for the IKDC total score and each domain of the CHQ. Correlations were classified as strong if greater than 0.5, moderate if 0.3 to 0.5, small if 0.1-0.3, and insubstantial if < 0.13. Moderate or strong correlations were further explored by calculating correlation between domains of the CHQ and each question on the IKDC. Further, specific domains of the CHQ that were significantly related to IKDC total score (emotional role, social limitations – physical, self esteem, and mental health) were studied to delineate which specific IKDC questions were most strongly correlated with each CHQ domain.
All data analysis was performed using Stata version 10 (College Station, Tx). For statistical significance testing of correlations between the IKDC and the CHQ Sidak’s adjustment was performed yielding an alpha of less than 0.005. Student’s unpaired t-test was used for comparisons of IKDC and CHQ scores between groups.
The IKDC Subjective Knee Evaluation form and the CHQ health related quality of life measure was completed by 135 patients with an ACL injury. The median age was 15.3 (range 13.1-17.2) and 59% (80/135) of respondents were male (Table 1). The majority of the patients sustained a complete midsubstance ACL rupture (90% (121/135)), while the remainder had a partial tear. Fifteen (11%) patients were treated non-operatively including all fourteen patients with a partial tear and one patient with a complete tear. Of the remaining operative patients, 42% completed the questionnaires pre-op, while 58% completed the surveys after ACL reconstruction.
Analysis of the entire group of patients yielded significant correlations between the IKDC total score and seven of twelve CHQ domains (Figure 1) including physical functioning (strong), emotional role (moderate), social limitations – physical (moderate), bodily pain (strong), mental health (moderate), self esteem (moderate), and family activities (moderate) ( p < 0.001 )(specific Spearman’s rho values were withheld secondary to pending publication in a peer reviewed journal). Correlations between CHQ domains dealing with emotional and social limitations including 1) emotional role, 2) social limitations – physical, 3) mental health, and 4) self esteem and each question of the IKDC was performed. The majority of the IKDC questions were significantly correlated to emotional role (14/20), mental health (14/20), and self esteem (14/20) with social limitations – physical having 9/20 correlated (Sidak-adjusted alpha = 0.0006). The mean total IKDC score for patients before surgery was 20.8 points lower than patients who completed the survey greater than 3 months after surgery (p<.0001) A comparison of pre-surgical patients with a complete ACL tear and those with a partial tear also yielded a statistically significant difference (p = 0.0005). Figure 2 demonstrates the mean total IKDC score as a function of time completed in relation to surgery.
The primary purpose of this study was to assess the impact of knee function as measured by the IKDC Subjective Knee Evaluation Form on various domains of physical and emotional well-being measured by the CHQ (CHQ – CF87) in pediatric and adolescent patients with an ACL injury. The IKDC has previously been validated in adult patients and has been shown to relate to concurrent measures of physical function, but not emotional function in adults9. We hypothesized that the IKDC would correlate not only with physical domains of the CHQ, but would also be related to emotional and social domains, suggesting a different impact of an ACL injury on a child as compared to an adult.
Our results indicate the total IKDC knee score significantly relates to quality of life in a group of 135 pediatric and adolescent patients in expected physical domains (physical functioning, bodily pain, family activities) in addition to social and emotional domains (emotional role, social limitations – physical, mental health, self esteem). A specific analysis of the previously mentioned social and emotional domains details a significant correlation to the majority of the IKDC individual questions. These results demonstrate that an ACL injury has a significant effect on the quality of life in young patients in physical, emotional, and social measures. This effect is demonstrated in patients treated non-operatively, in patients prior to surgery, and in post-operative patients.
Younger patients may deal with injury differently than adults and may have more difficulty with identity transition and coping secondary to the large role that sport (and lack of participation in) contributes to their self esteem and identity. Therefore, certain patients may benefit from a referral to a sports psychologist to assist with comeback strategies, coping strategies, and stress reconditioning. The practicing orthopaedic surgeon should be aware of the psychosocial impact of injury in this population, inform the patient and family, inquire about difficulties with coping or adjustment, and consider referral. Those patients on a high level athletic trajectory, patients with intense parental involvement, perceived guilt over their injury, or with a unilateral focus on sport without other extracurricular involvement may be appropriate for consultation.
Prior studies have demonstrated normative pilot data for the IKDC similar to that of adults age 35 and younger22, but the psychometric properties had not been established and its validity and comprehensibility was been previously questioned11. However, one recent study has shown the IKDC to be valid and consistent in a group of patients age 6-1820, and another has demonstrated the IKDC to be valid, reliable, and responsive in the pediatric population with knee disorders14. In our select population of patients aged 13-17 with an ACL tear, the internal consistency was > 0.90 (Cronbach’s alpha). In addition, the IKDC successfully differentiated patients pre- and post-operatively as well as partial and complete ACL tear.
In pediatric and adolescent patients with an ACL tear, seven of the twelve domains on the CHQ are significantly correlated with the IKDC. In addition to physical functioning, bodily pain, and social limitations – physical; the domains of esteem, mental health, emotional role, and social limitations categories are significantly correlated with knee function suggesting that quality of life in this population is affected in categories outside of physical function and pain. Pediatric patients are affected differently than adults by ACL injuries and a greater understanding of the psychosocial impact of injury may be of utility in these patients.
1. Anderson AF, Irrgang JJ, Kocher MS, Mann BJ, Harrast JJ. The International Knee Documentation Committee Subjective Knee Evaluation Form: normative data. Am J Sports Med. 2006;34(1):128-135.
2. Barnes PM, Price L, Maddocks A, Lyons RA, Nash P, McCabe M. Unnecessary school absence after minor injury: case-control study. BMJ. 2001;323(7320):1034-1035.
3. Cohen J. Statistical power analysis for the behavioral sciences (2nd edition). . Hillsdale, NJ: Erlbaum; 1988.
4. Freedman KB, Glasgow MT, Glasgow SG, Bernstein J. Anterior cruciate ligament injury and reconstruction among university students. Clin Orthop Relat Res. 1998(356):208-212.
5. Hambidge SJ, Davidson AJ, Gonzales R, Steiner JF. Epidemiology of pediatric injury-related primary care office visits in the United States. Pediatrics. 2002;109(4):559-565.
6. HealthACTCHQ. CHQ Scoring and Interpretation Manual. Vol http://www.healthactchq.com/survey-chq.php: HealthACTCHQ; 2008.
7. Hemingway H, Stafford M, Stansfeld S, Shipley M, Marmot M. Is the SF-36 a valid measure of change in population health? Results from the Whitehall II Study. BMJ. 1997;315(7118):1273-1279.
8. Hyman JE, Jewetz ST, Matsumoto H, Choe JC, Vitale MG. Risk factors for school absence after acute orthopaedic injury in new york city. J Pediatr Orthop. 2007;27(4):415-420.
9. Irrgang JJ, Anderson AF, Boland AL, et al. Development and validation of the international knee documentation committee subjective knee form. Am J Sports Med. 2001;29(5):600-613.
10. Irrgang JJ, Anderson AF, Boland AL, et al. Responsiveness of the International Knee Documentation Committee Subjective Knee Form. Am J Sports Med. 2006;34(10):1567-1573.
11. Iversen MD, Lee B, Connell P, Andersen J, Anderson AF, Kocher MS. Validity and comprehensibility of the International Knee Documentation Committee Subjective Knee Evaluation form in Children. Scand J Med Sci Sports. 2010;20(1):e87-95.
12. Janarv PM, Nystrom A, Werner S, Hirsch G. Anterior cruciate ligament injuries in skeletally immature patients. J Pediatr Orthop. 1996;16(5):673-677.
13. Joos R, Ruperto N, Wouters C, et al. The Belgian-Flemish version of the Childhood Health Assessment Questionnaire (CHAQ) and the Child Health Questionnaire (CHQ). Clin Exp Rheumatol. 2001;19(4 Suppl 23):S20-24.
14. Kocher MS, Smith JT, Iversen MD, et al. Reliability, Validity, and Responsiveness of a Modified International Knee Documentation Committee Subjective Knee Form (Pedi-IKDC) in Children With Knee Disorders. Am J Sports Med. 2010.
15. McCarroll JR, Rettig AC, Shelbourne KD. Anterior cruciate ligament injuries in the young athlete with open physes. Am J Sports Med. 1988;16(1):44-47.
16. Micheli LJ. Sports injuries in children and adolescents. Questions and controversies. Clin Sports Med. 1995;14(3):727-745.
17. Raat H, Bonsel GJ, Essink-Bot ML, Landgraf JM, Gemke RJ. Reliability and validity of comprehensive health status measures in children: The Child Health Questionnaire in relation to the Health Utilities Index. J Clin Epidemiol. 2002;55(1):67-76.
18. Raat H, Landgraf JM, Bonsel GJ, Gemke RJ, Essink-Bot ML. Reliability and validity of the child health questionnaire-child form (CHQ-CF87) in a Dutch adolescent population. Qual Life Res. 2002;11(6):575-581.
19. Ruperto N, Ravelli A, Pistorio A, et al. Cross-cultural adaptation and psychometric evaluation of the Childhood Health Assessment Questionnaire (CHAQ) and the Child Health Questionnaire (CHQ) in 32 countries. Review of the general methodology. Clin Exp Rheumatol. 2001;19(4 Suppl 23):S1-9.
20. Schmitt LC, Paterno MV, Huang S. Validity and internal consistency of the international knee documentation committee subjective knee evaluation form in children and adolescents. Am J Sports Med. 2010;38(12):2443-2447.
21. Shea KG, Pfeiffer R, Wang JH, Curtin M, Apel PJ. Anterior cruciate ligament injury in pediatric and adolescent soccer players: an analysis of insurance data. J Pediatr Orthop. 2004;24(6):623-628.
22. Slobogean GP, Mulpuri K, Reilly CW. The International Knee Documentation Committee Subjective Evaluation Form in a preadolescent population: pilot normative data. Am J Sports Med. 2008;36(1):129-132.
23. Trentacosta NE, Vitale MA, Ahmad CS. The effects of timing of pediatric knee ligament surgery on short-term academic performance in school-aged athletes. Am J Sports Med. 2009;37(9):1684-1691.
24. Waters E, Salmon L, Wake M. The parent-form Child Health Questionnaire in Australia: comparison of reliability, validity, structure, and norms. J Pediatr Psychol. 2000;25(6):381-391.
25. Waters EB, Salmon LA, Wake M, Wright M, Hesketh KD. The health and well-being of adolescents: a school-based population study of the self-report Child Health Questionnaire. J Adolesc Health. 2001;29(2):140-149.
26. Wulffraat N, van der Net JJ, Ruperto N, et al. The Dutch version of the Childhood Health Assessment Questionnaire (CHAQ) and the Child Health Questionnaire (CHQ). Clin Exp Rheumatol. 2001;19(4 Suppl 23):S111-115.
Posted on January 2, 2012, in Clinical and tagged ACL Tears. Bookmark the permalink. Comments Off on Correlation between the Child Health Questionnaire and the International Knee Documentation Committee score in pediatric and adolescent patients with an anterior cruciate ligament tear.