Kan H. Mak

Clinical effectiveness of school screening for adolescent idiopathic scoliosis: A large population-based retrospective cohort study

Study Design. Retrospective cohort study. Objective. To evaluate the clinical effectiveness of school scoliosis screening using a large and long–term-followed cohort of students in Hong Kong. Summary of Background Data. School screening for adolescent idiopathic scoliosis has been criticized as resulting in over-referrals for radiography and having low predictive values. Indeed, all but one previous retrospective cohort studies had no follow-up assessments of students until their skeletal maturity, leaving any late-developed curves undetected. The one study that completed this follow-up was well conducted but had low precisions due to its small sample size. Methods. A total of 157,444 students were eligible for a biennial scoliosis screening, and their screening results and medical records up to 19 years of age were available. Students first had forward bending test and angle of trunk rotation (ATR) performed. Those with ATR between 5° and 14° or signs of adolescent idiopathic scoliosis were assessed by moiré topography regularly. Students with an ATR ≥15°, ≥2 moiré lines, or significant clinical signs were referred for radiography and had their Cobb angle measured. Results. Of the 115,190 screened students in the cohort, 3228 (2.8%, 95% confidence interval [CI] = 2.7%–2.9%) were referred for radiography. At the final follow-up, the positive predictive values were 43.6% (41.8%–45.3%) for a Cobb angle ≥20° and 9.4% (8.4%–10.5%) for needing treatment, while the sensitivities were 88.1% (86.4%–89.6%) and 80.0% (75.6%–83.9%), respectively. Conclusion. This is the largest study that has demonstrated that school scoliosis screening in Hong Kong is predictive and sensitive with a low referral rate. Screening should thus be continued in order to facilitate early administration of conservative treatments.

Referral criteria for school scoliosis screening: assessment and recommendations based on a large longitudinally followed cohort.

Study Design. This study was a retrospective cohort study. Objective. To examine the criteria recommended in the literature for the school-based scoliosis screening program in Hong Kong. Summary of Background Data. School-based screening for scoliosis has been a controversy. Objectors to the policy were concerned about the high over-referral and false-positive rates. Recommendations were then made for improvement, but the feasibility of these recommendations has not been studied. Methods. The cohort consisted of students in Grade 5 in 1995/1996 or 1996/1997 who underwent scoliosis screening in Hong Kong. Participants who had an angle of trunk rotation (ATR) ≥15°, 2 or more moiré lines, or presented significant clinical signs were referred for radiography. Screening histories and radiography records before the age of 19 years were extracted. The accuracy measures for different combinations of screening tests were examined. Results. There were 115,178 students in the cohort, of which 3228 (2.8%) were referred for radiography. Among the 1406 students who displayed a curve ≥20° during screening, 257 (18.3%) were boys and 336 (23.9%) were identified as 16 years or older, ruling out the suggestion of screening only 10-year-old girls. The sensitivity and positive predictive value for the current referral criteria were 88.1% and 43.6%, respectively. The sensitivity would drop substantially if the use of moiré topography (39.8%) or clinical signs (55.5%) were discarded. With the inclusion of these 2 tests, the clinical effectiveness measures were robust to the cutoff for ATR, unless it was set below 10°. Conclusion. Selectively screening only premenarche girls was not feasible, as this screen would have missed a significant proportion of children with significant curvature. No refinement of the current protocol was necessary, although boys could be screened beginning at 12 years of age. The tandem use of ATR, moiré topography, and clinical signs was recommended for future studies.

FEAR OF MOVEMENT/(RE)INJURY IN CHINESE PATIENTS WITH CHRONIC PAIN: FACTORIAL VALIDITY OF THE CHINESE VERSION OF THE TAMPA SCALE FOR KINESIOPHOBIA

OBJECTIVE To assess the factor structure of the Chinese version of the Tampa Scale for Kinesiophobia (TSK). DESIGN Chinese patients with chronic pain attending either orthopaedic specialist services (n = 216) or multidisciplinary specialist pain services (n = 109) participated in this study. METHODS Subjects completed the Chinese version of TSK, The Chronic Pain Grade Questionnaire, Hospital Anxiety and Depression Scale, and questions assessing socio-demographic characteristics. Confirmatory factor analyses were used to compare hierarchical and correlated models of 5 different factor solutions previously reported in patients with chronic pain in the West. RESULTS Confirmatory factor analyses demonstrated inequality of the TSK factor structure, in that the TSK11 for the orthopaedics sample was best represented by a two-factor correlated model (S-Bchi2 = 49.593; comparative fit index (CFI) = 0.93; normed filt index (NFI) = 0.911; root mean square error of approximation (RMSEA) = 0.025) comprising 2 first-order factors, Somatic Focus (TSK11-SF) and Activity Avoidance (TSK-AA). The pain clinic sample showed a one-factor structure as best representing the TSK4s underlying dimensions (CFI = 0.971; NFI = 0.912; RMSEA = 0.048). There was no evidence to support a single overarching concept of kinesiophobia. CONCLUSION The TSK appears to have utility in Chinese chronic pain populations. Elucidation of the TSKs psychometrics properties in other Chinese/Asian pain populations with different diagnoses and presentations of pain problems is warranted.

Assessing depression in patients with chronic pain: a comparison of three rating scales.

BACKGROUND Considerable evidence has suggested depression is significantly more prevalent in patients with chronic pain. A number of studies exclusively based on Western samples have evaluated the effectiveness of depression rating scales in assessing depression in the chronic pain context. The objective of this cross-sectional study was to compare within a Chinese chronic pain sample three depression rating scales commonly used in identifying depression. METHODS A total of 366 Chinese patients with chronic pain attending either an orthopedic specialist clinic (n=185) or a multidisciplinary pain clinic (n=181) in Hong Kong completed a structured interview using CIS-R and two depression rating scales, the Beck Depression Inventory (BDI standard and short form) and the Center for Epidemiological Studies-Depression (CES-D). Patient scores on the BDI and CES-D were then assessed against their responses on the CIS-R to determine their effectiveness. RESULTS The prevalence of depression was 20.2% and 57.8% in the Orthopedics and Pain Clinic sample respectively. Results of ROC analyses showed that all the three measures performed well at predicting depression with AUC ≥ 0.89 and high sensitivity and specificity. CONCLUSIONS Our findings suggest that the three depression measures assessed have good predictive validity in the Chinese chronic pain context, and they could be used as screening or diagnostic measures of depression in Chinese chronic pain patients. The decision of using a specific measure and a specific cutoff score should be based on study aim and setting.

Costs of school scoliosis screening: a large, population-based study.

Study Design. This was a population-based retrospective study. Objective. To fully estimate the costs of the Hong Kong scoliosis screening program through a large, population-based study. Summary of Background Data. School screening for scoliosis has often been criticized for having high costs. In fact, the screening cost that has reported varied widely, from less than 1 to more than 30 US dollars (USD) per child screened. This variation is mainly due to the incomplete inclusion of cost items. Methods. We examined the screening and medical histories of a cohort of 115,190 screened students who were in Grade 5 in 1995/96 or 1996/97. The average costs spent on screening, diagnosing, following, and treating this cohort of students were calculated. Results. The total expenses in the screening centers increased steadily from USD 380,930 in 1995/96 to USD 2,417,824 in 2005/06. Based on the 115,190 students who were followed up until they were 19 years old or they left school, the costs of screening and diagnosing 1 student during adolescence were USD 17.94 and USD 2.08, respectively. Of the 1311 referrals who attended the specialist hospitals for diagnosis, 264 and 39 had been braced and operated on, respectively. The medical care cost averaged USD 34.61 per student screened. The cost of finding 1 student with a curvature ≥20° and 1 treated case were USD 4475.67 and USD 20,768.29 respectively. Conclusion. This was the largest study that has evaluated school scoliosis screening on students who were followed during their adolescence and accounted for all relevant costs. The cost per student screened in the scoliosis screening program in Hong Kong was comparable to that in Rochester, which had a similar protocol and was evaluated in a similar manner. The estimated costs can help the policy makers when they allocate healthcare resources.

Assessing Attitudes Toward and Beliefs About Pain Among Chinese Patients with Chronic Pain: Validity and Reliability of the Chinese Version of the Pain Beliefs and Perceptions Inventory (ChPBPI)

CONTEXT Research consistently has evidenced the reliability and validity of the Pain Beliefs and Perceptions Inventory (PBPI). The instrument, however, has not been tested for its applicability and validity in non-Western populations. OBJECTIVES To translate the English language version of the PBPI into Chinese (ChPBPI) and to evaluate its reliability, validity, and factor structure. METHODS A total of 208 Chinese patients with mixed origin chronic pain were recruited from an orthopedic specialist outpatient clinic associated with a public hospital in Hong Kong. In addition to the ChPBPI, patients were administered the Chronic Pain Grade (CPG) questionnaire, the Pain Catastrophizing Scale (PCS), the Center for Epidemiological Studies-Depression Scale (CES-D), and questions assessing sociodemographic characteristics. RESULTS Using the original factor structure of the PBPI as a model, confirmatory factor analyses revealed that all four ChPBPI scales demonstrated good data-model fit (CFI≥0.92) and adequate internal consistency (Cronbachs αs: 0.60-0.76). The four ChPBPI scales showed significant positive correlations with CES-D, PCS, pain intensity, and disability. Results of hierarchical multiple regression analyses showed that the ChPBPI scales predicted concurrent depression (F(4, 187)=6.01, P<0.001), pain intensity (F(4, 186)=4.61, P<0.01), and pain disability (F(4, 190)=3.54, P<0.05) scores. CONCLUSION These findings support the factorial validity of the scales of the ChPBPI, and its reliability and construct validity. Now clinically relevant beliefs about pain can be assessed among Chinese patients with chronic pain.

Pain-Related Beliefs Among Chinese Patients with Chronic Pain: The Construct and Concurrent Predictive Validity of the Chinese Version of the Survey of Pain Attitudes-14 (ChSOPA-14)

CONTEXT Pain beliefs as indexed by the Survey of Pain Attitudes (SOPA) have been consistently shown to predict pain adjustment outcomes in Western populations. However, its utility in non-Western populations is unclear. OBJECTIVES We evaluated the construct and predictive validity of the Chinese version of the 14-item SOPA (ChSOPA-14) in a sample of Chinese patients with chronic pain. METHODS A total of 208 Chinese patients with chronic musculoskeletal pain completed the ChSOPA-14, the Chronic Pain Grade questionnaire, the Pain Catastrophizing Scale, the Center for Epidemiological Studies-Depression Scale, and measures of sociodemographic characteristics. RESULTS Except Medical Cure, all ChSOPA-14 scales were significantly correlated with validity criterion measures (all P<0.05) in expected directions. The present Chinese sample scored the highest on the Medical Cure scale (mean=2.98, standard deviation [SD]=1.05) but the lowest on the Disability scale (mean=1.75, SD=1.67). Results of hierarchical multiple regression analyses showed that the ChSOPA-14 scales predicted concurrent depression (F(7,177)=14.51, P<0.001) and pain disability (F(7,180)=8.77, P<0.001). Pain Control (stdβ [standardized beta coefficient]=-0.13; 95% confidence interval [CI]: -3.41, -0.13; P<0.05) and Emotion (stdβ=29; 95% CI: 1.76, 5.02; P<0.001) emerged as significant independent predictors of concurrent depression whereas Disability (stdβ=0.19; 95% CI: 1.33, 7.88; P<0.01), Emotion (stdβ=16; 95% CI: 0.08, 7.59; P<0.05), and Solicitude (stdβ=-0.14; 95% CI: -7.05, -0.04; P<0.05) significantly associated with concurrent disability. CONCLUSION The findings offer preliminary evidence for the construct and concurrent predictive validity of the ChSOPA-14. This makes available a suitable instrument for chronic pain in the Chinese population and will facilitate future cross-cultural research on pain beliefs.

Preliminary psychometric properties of the Chinese version of the Chronic Pain Coping Inventory (ChCPCI) in a Hong Kong Chinese population.

UNLABELLED The Chronic Pain Coping Inventory (CPCI) is a frequently used measure that assesses 8 categories of coping strategies that patients might use to cope with chronic pain. Despite its good psychometric properties and widespread use, the instrument has not been tested for its applicability and validity in non-Western populations, such as among Chinese. This study evaluated the reliability and validity of a Chinese translation of the 42-item CPCI (ChCPCI-42) in a sample of Chinese patients with chronic pain (n = 208). In addition to the ChCPCI-42, the patients were administered the Chronic Pain Grade (CPG) questionnaire, the Pain Catastrophizing Scale (PCS), the Centre for Epidemiological Studies-Depression Scale (CES-D), and questions assessing sociodemographic characteristics. Results of confirmatory factor analyses revealed that of the ChCPCI-42 8 scales, 6 demonstrated acceptable-to-good data-model fit (CFI >or= 0.90) and 2 demonstrated medium fit (CFI >or= 0.85). The 8 scales demonstrated adequate to good internal consistency (Cronbach alpha, 0.69 to 0.79) and correlated with CES-D, PCS, pain intensity, and disability in expected directions. Results of hierarchical multiple regression analyses showed that the ChCPCI-42 scales predicted concurrent depression (F (8,177) = 3.07, P < .01) and pain disability (F (1, 179) = 4.35, P < .001) scores, the Task Persistence scale being the strongest unique predictor among the 8 scales. The findings support the factorial validity and reliability of a 42-item CPCI that can be used among Chinese patients with chronic pain. PERSPECTIVE The report outlines the first validation of the CPCI for use in Hong Kong Chinese. This makes available a suitable instrument for chronic pain research in the Southern Chinese population and will help to elucidate similarities and differences in pain coping between Chinese and other ethnic groups.

Cost of school scoliosis screening: a cohort analysis of 306,144 students followed until skeletal maturity

Introduction: Palliative posterior decompression and instrumentation surgeries for spinal metastasis are effective in improving quality of life by providing good pain control and neurologic improvement. Preoperative embolization is usually performed because excessive blood loss is one of the main complications during the surgery. However, none of these studies have measured the effect of embolization on intraoperative blood loss in a single operative procedure. Aim: The purpose of this study was to evaluate the effectiveness of preoperative embolization in palliative posterior decompression and instrumentation surgery for spinal metastasis. Patients and methods: Forty-five patients were included in this study. Between 2000 and 2010, the patients underwent a palliative posterior decompression and instrumentation as the primary surgery for spinal metastasis in thoracolumbar spine. Not all of the patients had bleeding diathesis. One to three vertebral levels were decompressed by laminectomy and aggressive debulking of vertebral tumor. Five to seven vertebrae were stabilized using posterior instrumentation. Preoperative embolization was carried out on 23 patients (embolization group). In the embolization group, the primary tumors were in lung (7 patients), breast (4 patients), kidney (4 patients), prostate (2 patients) and the others (6 patients). The surgeries were carried out within 3 days after the embolization. The embolic materials were gelatin sponge, polyvinyl alcohol foam and metallic coils. The other 22 patients did not have the embolization (no embolization group). In the no embolization group, the primary tumor were in lung (8 patients), prostate (3 patients), colon (3 patients), breast (2 patients), the others (6 patients). Results: Angiographyandembolizationwasperformed inall 23patients in the embolization group without causing neurologic deficit. The pain and neurologic symptoms in all 45 patients were relieved after their surgery. The average intraoperative blood loss was 520 ml (140-1380 ml) in the embolization group. This was significantly lower than 1059 ml (100-3260 ml) in the no embolization group (p\0.05). In the embolization group, the intraoperative blood loss was not correlated with tumor vascularization degree, embolization degree and time between embolization and surgery. Conclusion: The intraoperative blood loss, after preoperative embolization, was measured to be about the half of that without preoperative embolization.