The following letters are published as a response to the article, "The Effectiveness of School Scoliosis Screening" which appeared in JAMA http://jama.ama-assn.org/.

To The Editor:
I recently reviewed an article in The Journal of the American Medical Association¹⁸, in which an epidemiologist proposed that school scoliosis screening is no longer cost-effective. As an emeritus member of the orthopaedic community, I shudder at this proposition. I remember only too well the patients with grotesque curves whom I would see in my office in the 1960s prior to the advent of screening examinations. Children with curves requiring treatment included the offspring of physicians, much to their consternation. The onset of idiopathic scoliosis among girls coincides with the premenarchal period of their development when their sense of secrecy and privacy is at its height. Parents could go from one swimming season to the next without seeing their child fully disrobed. Perhaps I'm naïve, but to me the cost of a school or public health nurse carrying out screening examinations among middle-school children could not possibly be a deterrent to this most effective form of public health oversight. In my professional lifetime, idiopathic scoliosis has become essentially a nonoperatively treated disease. I hope that all physicians, including pediatricians, pediatric orthopaedists, and general orthopaedists, who are interested in the well-being of our children will beat on our shields and raise a hue and cry to preserve this most simple and effective deterrent to a crippling condition. I think that scoliosis screening of preadolescent children would be a corollary to the maxim that 90 percent of disease can be diagnosed by obtaining a careful history and performing a thorough physical examination. Simple, straightforward concepts work the best but often are the most difficult to put into effect because of the vagaries of human nature.

Thomas F. Scott, M.D.
Scott Orthopedic Center
2828 First Avenue, Suite
400 P.O. Box 3127
Huntington, West Virginia 25702

S. L. Weinstein replies:
Dr. Scott's letter in response to the recently published article by Yawn et al.¹⁸ once again raises the question of the value of school screening for scoliosis; should it be done and is it cost effective?

Dr. Scott correctly points out the benefit of school screening programs instituted around the United States over the past 40 years: the earlier detection of children with curvature of the spine. These programs and the educational efforts that accompanied them no doubt increased the awareness among primary care physicians and lay persons about scoliosis and resulted in the earlier presentation for treatment of patients with curvature of the spine. It has also provided early diagnosis in patient populations who may not have access to primary health care. These programs have also given us the opportunity to learn more about the disorder. Despite these benefits, school screening as practiced in the United States has not been shown to be cost-effective and its justification and effectiveness have been questioned repeatedly.

Should school screening be done? Screening is the "presumptive identification of unrecognized disease or defects by the application of tests, examination or other procedures, which can be applied rapidly. Screening tests sort out apparently healthy persons who probably do not have a disease from those who probably do have the disease."^3,12 With reference to scoliosis, the U.S. Preventative Services Task Force report on screening for adolescent scoliosis was unable to reach a conclusion on the effectiveness of school screening due to lack of randomized controlled trials or observational studies of the outcomes^13,14. Other studies recommend against screening for scoliosis because of the low incidence of cases requiring treatment, the low positive predictive value of the screening programs, and the high number of false positives from these programs^2,4,8,9.

Morrissy has clearly delineated the issues related to school screening in two recent articles^11,12. He points out that while "…some will be selected for diagnosis who are found to be normal (false positive), and some will be presumed normal and not referred for diagnosis who actually have the disease (false negatives)... most screening programs have more false positives than negatives." The key question is: "are the anxiety, cost, and morbidity of the false positives worth the earlier detection of the true positives?"¹².

Epidemiologists and health care policy makers would agree that early detection of a disease, through a screening program, is important if the disease is prevalent and is an important health problem. This also assumes that the disease has a known natural history. The screening tests for the condition should have an adequate positive and negative predictive value. Screening tests should not be harmful to the individuals being screened. Another key element of a screening program is that an accepted effective treatment exists so that early detection improves prognosis. Finally, the screening process and subsequent treatment should be cost-effective from a societal perspective^6,9,17.

Unfortunately, screening for adolescent idiopathic scoliosis does not fulfill these criteria. The prevalence of patients with significant curves is very low. The overwhelming majority of curves are small and will remain so, and they are also generally asymptomatic. Only curves over 30 degrees, which constitute the minority, have the potential to become a health care problem to the individual^15,16.

The Yawn et al. population-based study reported a cumulative incidence of 1.8% over a fifteen-year period. Of the 2,242 children, 27 cases were definitively diagnosed. Nine of the twenty-seven cases required treatment (4 by a brace, one by surgery, and 4 by surgery after brace failure). The surgical rate in this series was 0.22%. In this study the positive predictive value of screening was 0.05% with 448 children needing to be screened to identify one child who subsequently required treatment¹⁸.

With respect to the non-radiographic tests used for screening (Adams forward-bend test, Moire fringe topography, and the scoliometer), most show a high number of false positive results; i.e., they are overly sensitive¹. In addition these tests are not specific and don't have a positive predictive value (impacted significantly by the low prevalence of the condition). These tests also lack sufficient data on intra-observer and inter-observer reliability¹¹.Screening without a validated screening test generates too many false positives.

It is also not clear that early detection alters the course of the disease.

Bracing is the accepted method of early treatment for curves between 25 and 40 degrees in immature patients. Controversy, however, exists as to its effectiveness. While there is some evidence to support the effectiveness of orthotic treatment¹⁰, there is other contradictory evidence⁵. There are also conflicting reports as to whether surgical rates are altered by screening programs. Most studies reporting the reduction in surgical rates are not population-based, and the results are difficult to generalize⁷.

Finally, screening for this condition is not cost-effective. Not all positively screened cases result in cost reduction, and secondly, when costs are determined, direct and indirect costs must be taken into account. As it is difficult to determine the direct and indirect costs of a screening program, as well as the benefits and morbidities associated with surgery and bracing, no cost-benefit analysis is possible¹¹.

In summary, I share Dr. Scott's concerns about the early detection of scoliosis; however, for the reasons stated above, school screening for adolescent idiopathic scoliosis does not meet the criteria generally accepted for prescriptive screening for disease.

Stuart L. Weinstein, M. D.
Ignacio V. Ponseti Chair of Orthopaedic Surgery
Department of Orthopaedic Surgery
University of Iowa Hospitals and Clinics
Iowa City
Iowa 52242
E-mail address for Dr. Weinstein:
stuart-weinstein@uiowa.edu

1. Amendt, L. E.; Ause-Ellias, K. L.; Eybers, J. L.; Wadsworth, C. T.; Nielsen, D. H.; and Weinstein, S. L.: Validity and reliability testing of the Scoliometer. Phys. Ther., 70: 108-117, 1990.

2. Berwick, D. M: Scoliosis screening. Pediat. Rev., 5: 238-247, 1985.

3. Commission on Chronic Illness: Prevention of chronic illness. In Chronic Illness in the United States, Vol. 1, p. 45. Cambridge, Massachusetts, Harvard University Press, 1957.

4. Dickson, R. A.; Stamper, P.; Sharp, A. M.; and Harker, P.: School screening for scoliosis: cohort study of clinical course. British Med. J., 281: 265-267, 1980.

5. Dickson, R. A., and Weinstein, S. L.: Bracing (and screening) - yes or no? J. Bone and Joint Surg., 81-B(2): 193-198, March 1999.

6. Frankenberg, W., and Camp, B.: Pediatric Screening Tests, pp. 9-22. Springfield, Illinois, Thomas, 1975.

7. Goldberg, C. J.; Dowling, F. E.; Fogerty,E. E.; and Moore, D. P.: School scoliosis screening and the United States Preventative Services Task Force. An examination of long-term results. Spine, 20: 1368-1374, 1995.

8. Karachalios, T.; Roidis, N.; Papagelopoulas, P. J.; and Karachalios, G. G.: The efficacy of school screening for scoliosis. Orthopedics, 23: 386-393, 2000.

9. Leaver, J. M.; Alvik, A.; and Warren, M. D.: Prescriptive screening for adolescent idiopathic scoliosis: a review of evidence. Internat. J. Epidemiol., 11: 101-111, 1982.

10. Lonstein, J. E., and Winter R. B.: The Milwaukee brace for the treatment of adolescent idiopathic scoliosis. A review of one thousand and twenty patients. J. Bone and Joint Surg., 76-A: 1207-1221, Aug. 1994.

11. Morrissy, R. T.: School screening for scoliosis. A statement of the problem. Spine, 13: 1195-1197, 1988.

12. Morrissy, R. T.: School screening for scoliosis. Spine, 24: 2584-2591, 1999.

13. Screening for adolescent idiopathic scoliosis. Policy statement. U. S. Preventative Services Task Force. J. Am. Med. Assn., 269: 2664-2666, 1993.

14. Screening for adolescent idiopathic scoliosis. Review article. U. S. Preventative Services Task Force. J. Am. Med. Assn., 269: 2667-2672, 1993.

15. Weinstein, S. L.; Zavala, D. C.; and Ponseti, I. V.: Idiopathic scoliosis: long-term follow-up and prognosis in untreated patients. J. Bone and Joint Surg., 63-A: 702-712, June 1981.

16. Weinstein, S. L., and Ponseti I. V.: Curve progression in idiopathic scoliosis. J. Bone and Joint Surg., 65-A: 447-455, April 1983.

17. Wilson, J. M. G., and Jungner, O.: Principles and Practice of Screening for Disease. Geneva, World Health Organization, 1968.

18. Yawn, B. P.; Yawn, R. A.; Hodge, D.; Kurland, M.; Shaughnessy, W. J; Ilstrup, D.; and Jacobsen, S. T.: A population-based study of school screening. J. Am. Med. Assn., 282: 1427-1432, 1999.