CONSENSUS STATEMENT BY THE AMERICAN ASSOCIATION OF CLINICAL ENDOCRINOLOGISTS AND AMERICAN COLLEGE OF ENDOCRINOLOGY ON THE QUALITY OF DXA SCANS AND REPORTS.

OBJECTIVE: High-quality dual-energy X-ray absorptiometry (DXA) scans are necessary for accurate diagnosis of osteoporosis and monitoring of therapy; however, DXA scan reports may contain errors that cause confusion about diagnosis and treatment. This American Association of Clinical Endocrinologists/American College of Endocrinology consensus statement was generated to draw attention to many common technical problems affecting DXA report conclusions and provide guidance on how to address them to ensure that patients receive appropriate osteoporosis care. METHODS: The DXA Writing Committee developed a consensus based on discussion and evaluation of available literature related to osteoporosis and osteodensitometry. RESULTS: Technical errors may include errors in scan acquisition and/or analysis, leading to incorrect diagnosis and reporting of change over time. Although the International Society for Clinical Densitometry advocates training for technologists and medical interpreters to help eliminate these problems, many lack skill in this technology. Suspicion that reports are wrong arises when clinical history is not compatible with scan interpretation (e.g., dramatic increase/decrease in a short period of time; declines in previously stable bone density after years of treatment), when different scanners are used, or when inconsistent anatomic sites are used for monitoring the response to therapy. Understanding the concept of least significant change will minimize erroneous conclusions about changes in bone density. CONCLUSION: Clinicians must develop the skills to differentiate technical problems, which confound reports, from real biological changes. We recommend that clinicians review actual scan images and data, instead of relying solely on the impression of the report, to pinpoint errors and accurately interpret DXA scan images. ABBREVIATIONS: AACE = American Association of Clinical Endocrinologists; BMC = bone mineral content; BMD = bone mineral density; DXA = dual-energy X-ray absorptiometry; ISCD = International Society for Clinical Densitometry; LSC = least significant change; TBS = trabecular bone score; WHO = World Health Organization.

Bone shortening of clavicular fractures: comparison of measurement methods.

BACKGROUND: The indication for operative treatment of clavicular fractures with bone shortening over 2 cm is much debated. Correct measurement of clavicular length is essential, and reliable measures of clavicular length are therefore highly requested by clinical decision-makers. The aim of this study was to investigate if three commonly scientifically used measurement methods were interchangeable to each other. METHODS: A retrospective study using radiographs collected as part of a previous study on clavicular fractures. Two independent raters measured clavicle shortening on 60 patients using conventional radiographs on two separate sessions. The two measurement methods described by Hill et al. and Silva et al. were used on unilateral pictures. Side difference measurements according to Lazarides et al. were made on panoramic radiographs. The measurements were analyzed using intraclass correlation, Weir's protocol for Standard error of measurement (SEM) and minimal detectable change (MDC), and Bland-Altman plots. RESULTS: None of the methods were directly interchangeable. The side difference method by Lazarides et al. was the most reliable of the three methods, but had a high proportion of post-fracture bone lengthening that indicated methodological problems. The Hill et al. and Silva et al. methods had high minimal detectable change, making their use unreliable. CONCLUSION: As all three measurement methods had either reliability or methodological issues, we found it likely that differences in measurement methods have caused the differences in clavicular length observed in scientific studies.

An analysis of the most common types of hand injury mistakes and their cost in the acute setting.

This study aimed to explore the most common hand injury errors occurring in Emergency Departments in England. A Freedom of Information request was made to the NHS Litigation Authority for claims data related to hand injuries in English Emergency Departments from 2004 to 2014. All successful hand injury claims against an individual DGH ED were also analysed. Two hundred and eighteen successful claims were made, costing a total of £6,273,688.22. Diagnosis error was the most common successful claim (97). Four successful claims were brought against the Emergency Department. Causes of error included the use of inappropriate views and failure to correlate imaging with clinical findings. Hand injury diagnostic error has been the most common cause of successful litigious claims against Emergency Departments over the past 10 years. This paper demonstrates that fracture recognition and clinical diagnosis of hand injuries are key areas to target to reduce error rates.

Peligrosidad de los componentes del paquete radiográfico intraoral y líquidos de procesado / Danger of the intraoral radiographic package and developer liquid components

En odontología, para la obtención de imágenes radiográficas intraorales por métodos convencionales, se utilizan paquetes radiográficos que contienen en su interior a la película radiográfica. Luego de la exposición del paquete radiográfico a los rayos X se realiza el procesado, lo cual requiere el uso de líquidos reveladores y fijadores, que son las sustancias químicas que harán posible la visualización de la imagen.Tanto el paquete radiográfico como lo líquidos de procesado presentan en su constitución elementos que, por sus características, pueden ser incluidos enel rubro de “elementos peligrosos” para la salud y para el medio ambiente. En este trabajo de divulgación se pretende realizar un análisis de las características que hacen a la peligrosidad de cada uno de los componentes del paquete radiográfico y de los líquidos —revelador y fijador— usados en el procesado, lo cual es necesario conocer para el manejo seguro y adecuado de este tipo de elementos...

Evaluation of different techniques for CT radiation profile width measurement.

This work has been conducted to demonstrate a procedure for using a Konica Minolta computed radiography (CR) system for the measurement of computed tomography (CT) radiation profile width, and to compare this method with conventional and GAFCHROMIC XR-QA2 film measurements. The exposure and processing conditions of a Konica Minolta CR reader system were characterized to establish the relationship between exposure at the imaging plate (IP) and pixel value. A 6 cc ionization chamber was exposed at the isocenter of a CT scanner using 80 kVp, 0.4 sec with various mA settings. CR images were processed in fixed modes with various combinations of S and G values, establishing exposure and pixel value relationships. Appropriate exposure techniques and processing parameters were selected to avoid the saturation of the IP. Using the selected exposure and processing parameters, radiation profiles of various nominal collimation settings (40, 20, 10, and 5 mm) were acquired for measurement. Radiochromic film was characterized and utilized to compare with CR profiles and profiles obtained via conventional film. Appropriate exposures for both CR (80 kVp, large body filter, 4 and 8 mAs) and radiochromic films (120 kVp, large body filter, 300 mAs) were determined. Recommended CR processing settings (fixed mode with S = 5 and G= 1.81) were also determined. Compared to the conventional film results, the full width at half maximum (FWHM) results for CR agreed well within ± 10%, while radiochromic film results showed maximum deviations of about 5%. In conclusion, FWHM of CT radiation profiles can be conveniently and accurately measured using a Konica Minolta CR system or XR-QA2 film when appropriate exposure technique and processing parameters are used.

Compatibility characteristics of five radiographic films utilised in Brazilian diagnostic radiology.

To evaluate the quality of the radiographic films in Brazil, according to the recommendations of ISO 9236-1, a radiographic images simulator was used. A study of the control of the quality in radiographic films was implemented. With regard to this study, the results of five films of different manufacturers are presented. The characteristic curves for the ISO qualities of 55, 70, 90 and 120 kV are presented. The PTW REX simulator was used to determine the image quality parameters. Film 2 presents problems due to high sensitivity. Film 1 has a higher energy dependence than the other films. Film 5 yields the best results for almost all the sensitometric parameters. In conclusion, existing films in the Brazilian market vary considerably with relation to image quality.

Radiation protection in dental X-ray surgeries--still rooms for improvement.

AIM: To illustrate the authors' experience in the provision of radiation protection adviser (RPA)/medical physics expert (MPE) services and critical examination/radiation quality assurance (QA) testing, to demonstrate any continuing variability of the compliance of X-ray sets with existing guidance and of compliance of dental practices with existing legislation. METHOD: Data was collected from a series of critical examination and routine three-yearly radiation QA tests on 915 intra-oral X-ray sets and 124 panoramic sets. Data are the result of direct measurements on the sets, made using a traceably calibrated Unfors Xi meter. The testing covered the measurement of peak kilovoltage (kVp); filtration; timer accuracy and consistency; X-ray beam size; and radiation output, measured as the entrance surface dose in milliGray (mGy) for intra-oral sets and dose-area product (DAP), measured in mGy.cm(2) for panoramic sets. Physical checks, including mechanical stability, were also included as part of the testing process. RESULTS: The Health and Safety Executive has expressed concern about the poor standards of compliance with the regulations during inspections at dental practices. Thirty-five percent of intra-oral sets exceeded the UK adult diagnostic reference level on at least one setting, as did 61% of those with child dose settings. There is a clear advantage of digital radiography and rectangular collimation in dose terms, with the mean dose from digital sets 59% that of film-based sets and a rectangular collimator 76% that of circular collimators. The data shows the unrealised potential for dose saving in many digital sets and also marked differences in dose between sets. CONCLUSION: Provision of radiation protection advice to over 150 general dental practitioners raised a number of issues on the design of surgeries with X-ray equipment and critical examination testing. There is also considerable variation in advice given on the need (or lack of need) for room shielding. Where no radiation protection adviser (RPA) or medical physics expert (MPE) appointment has been made, there is often a very low level of compliance with legislative requirements. The active involvement of an RPA/MPE and continuing education on radiation protection issues has the potential to reduce radiation doses significantly further in many dental practices.

Evaluation of the efficacy of the guideline on reading CT images of malignant pleural mesothelioma with reference CT films for improving the proficiency of radiologists.

PURPOSE: To assess the efficacy of the developed guideline on reading CT images of malignant pleural mesothelioma for improving radiologists' reading proficiency. MATERIALS AND METHODS: Three radiologists independently read the CT films of 22 cases including definite mesothelioma and non-mesothelioma cases at two times before and after studying the malignant pleural mesothelioma CT Guideline. The sensitivity and specificity for mesothelioma were calculated and compared between the 1st and 2nd trials. The kappa statistics was examined for agreement with experts for mesothelioma probability and for mesothelioma features recorded by three radiologists. RESULTS: After studying the mesothelioma CT Guideline, the sensitivity for mesothelioma shown by the three radiologists at the 2nd trial was 100%, 100% and 80%, which were higher than 80%, 85% and 60% at the 1st trial, respectively. The average kappa for agreement between radiologists and experts on dichotomized mesothelioma probability were 0.69 (good) at the 2nd trial vs. 0.38 (fair) at the 1st trial. The average kappa for the agreement with experts for each of 7 features by three radiologists were 0.52-0.80 at the 2nd trial, which were significantly higher than 0.34-0.58 at the 1st trial (Wilcoxon Signed Rank Test: P<0.01), and as to five features "unilateral pleural effusion", "nodular pleural thickening", "tumoral encasement of lung", "mediastinal pleural thickening", and "diminished lung", they achieved good agreement with average kappa of 0.61-0.80. CONCLUSION: The developed mesothelioma CT Guideline was suggested to have substantial effect in improving the radiologists' proficiency for reading CT images of mesothelioma, and may contribute to accurate diagnosis of mesothelioma.

Compliance of reviewing portal images on radiographic film vs an electronic medical record.

PURPOSE: Timely approval of weekly portal images is essential for quality patient care. Most departments stipulate that portal images should be reviewed within 1 to 2 business days after imaging. The purpose of this study was to compare compliance of reviewing portal images per departmental policy before and after implementing an electronic medical record (EMR). METHODS: The use of an EMR to review portal images was initiated at the investigators' institution in March 2010. Before this, portal images were reviewed on either radiographic film or printouts from machines equipped with electronic portal imaging. The EMR could be accessed remotely by any computer with direct access to the institution's network. Patients selected were those treated by attending physicians present before and after the switch to the EMR. Patients were randomly selected for review of their portal images from 2009 for radiographic film and March to June 2010 for portal images in the EMR. Violations of department policy included unsigned portal images, undated portal images, no date documented when signed by the attending physician, and portal images signed after >1 business day. Violations for each portal image counted only once, even if the portal image had multiple types of violations. RESULTS: A total of 411 portal images were evaluated. Two hundred four radiographic films taken on 22 different patients were hand signed by 6 different attending physicians. Two hundred seven portal images taken on 16 different patients were reviewed via the EMR by the same 6 attending physicians. Twenty-five percent (51 of 204) of portal images reviewed by hand on radiographic films incurred violations, while 1% (2 of 207) of portal images reviewed via the EMR incurred violations. When portal images were reviewed by hand, 16 (8%) did not have the film date documented when taken by the therapists, 2 (1%) did not have documentation of date signed, 16 (8%) were never signed, and 17 (8%) were signed after 1 business day. All violations incurred with the EMR were for films signed after >1 business day. Chi-square analysis showed a significant improvement in compliance with reviewing portal films with the EMR (P < .001). CONCLUSIONS: The use of an EMR for reviewing portal images dramatically improved compliance with timeliness and record keeping. Timeliness of reviewing portal images improves patient care and safety.

Reject analysis in direct digital radiography.

BACKGROUND: Reject analysis can be used as a quality indicator, and is an important tool in localizing areas where optimization is required. Reducing number of rejects is important yielding reduced patient exposure and increased cost-effectiveness. PURPOSE: To determine rejection rates and causes in direct digital radiography. MATERIAL AND METHODS: Data were collected during a three-month period in spring 2010 at two direct digital laboratories in Norway. All X-ray examinations, types, numbers, and reasons for rejections were obtained using automatic reject analysis software. Thirteen causes for rejection could be selected. RESULTS: Out of the 27,284 acquired images, 3206 were rejected, yielding an overall rejection rate of 12%. Highest rejection rates were found for examination of knees, shoulders, and wrist. In all, 77% of the rejected images arose from positioning errors. CONCLUSION: An overall rejection rate of 12% indicates a need for optimizing radiographic practice in the department.

A quality control programme for medical X-ray films in India.

Medical X-ray films are continued to be the major image receptors in diagnostic radiology in India. About 9×106 m² of medical X-ray films are used per annum for diagnostic imaging in India, and its magnitude may further increase as the number of diagnostic X-ray units is increasing rapidly. A national quality control programme was initiated for testing the medical X-ray films of various suppliers/manufacturers so that optimum quality film can only be used in diagnostic radiography examinations. X-ray laboratory of Radiological Physics and Advisory Division, Bhabha Atomic Research Centre was recognised as national film testing laboratory. A dedicated test phantom was fabricated as per the prescription of International Organization for Standardization (ISO 9236-I, 1996), simulating the attenuation and scatter properties of chest of an average patient for periodic X-ray sensitometric evaluations of the medical X-ray films. The basic fog, speed, latitude, maximum optical density, uniformity and artefacts of all the films tested so far were found well within the requirements specified in the national standards. The average gradient for a few blue and green sensitive films were found less than the specified value. Suppliers/manufacturers of such films were advised to improve the performance quality of their films.

A comparative evaluation of film and digital panoramic radiographs in the assessment of position and morphology of impacted mandibular third molars.

BACKGROUND AND OBJECTIVE: Digital photo stimulable phosphor (PSP)-based radiography has many known theoretical advantages over conventional film radiography but its diagnostic efficacy has to be assessed clinically. This study compared the efficiency of conventional film-based panoramic radiographs with that of digital PSP-based panoramic radiographs in the assessment of position and morphology of impacted mandibular third molars. MATERIALS AND METHODS: We selected a total of 80 impacted mandibular third molars that fulfilled the inclusion and exclusion criteria of this study. Both conventional film-based panoramic radiographs and digital PSP-based panoramic radiographs were taken of all the study samples and the teeth were later surgically removed. Conventional film-based and digital PSP-based panoramic radiographs were compared for their relative efficiencies in the assessment of impaction status, position of tooth, number of roots, root morphology, and proximity to mandibular canal of impacted mandibular third molars. An oral surgeon graded these same factors during/after surgical exploration and this assessment was considered the gold standard. The data obtained were statistically analyzed using descriptive statistics, chi-square test, and McNemar's test. RESULTS: There was no statistically significant difference between conventional film-based radiographic assessment and digital PSP-based panoramic radiographic assessment of impaction status, position of tooth, number of roots, and proximity to mandibular canal of impacted mandibular third molars (P>0.05). However, there was significant difference between the two methods with regard to assessment of root morphology of impacted mandibular third molars (P=0.00). INTERPRETATION AND CONCLUSION: Conventional film-based panoramic radiographs and digital PSP-based panoramic radiographs were comparable in their accuracy in the preoperative study of impacted mandibular third molar with regard to impaction status, tooth position, number of roots, and proximity to the mandibular canal. Digital PSP-based panoramic radiographs were more accurate than conventional film-based panoramic radiographs in the assessment of root morphology of impacted mandibular third molars. Hence, we conclude that digital PSP-based panoramic radiographs can be used as an effective alternative to conventional film-based panoramic radiographs for assessment of position and morphology of impacted mandibular third molars.

Avaliação do padrão das radiografias periapicais realizadas no CEO de Endodontia da Faculdade de Odontologia de Caruaru-PE / Evaluation of the standard of the periapical radiographs taken at the CEO of Endodontics of the Faculty of Odontology of Caruaru-PE

O exame clínico juntamente com o exame radiográfico constitui peças chaves no estabelecimento do diagnóstico em vários procedimentos na Odontologia. A radiografia periapical representa um tipo de exame radiográfico bastante utilizado como método auxiliar no diagnóstico, que permite ao profissional um planejamento mais seguro da execução do tratamento, proservação e documentação de um modo geral. Contudo, para uma interpretação correta e segura, há a necessidade de radiografias padronizadas e de qualidade que possibilitem o estabelecimento de um diagnóstico adequado. Levando esses aspectos em consideração, a radiografia periapical deverá estar bem processada para que assim possa oferecer detalhes da área radiografada. Diante disso, esse estudo tem como objetivo avaliar o padrão das radiografias realizadas no CEO de Endodontia da Faculdade de Odontologia de Caruaru – PE no período de 2004 a 2007. Foram analisadas 460 radiografias nas quais se constatou que os principais erros encontrados foram: acondicionamento (71,96%), lavagem (37,17%), posicionamento da película radiográfica (33,04%), oxidação (31,52%), erros de processamento (claras 23,04% e escuras 5,7%), dentre outros. No final, verificou-se um alto índice de erros e um mínimo percentual de radiografias consideradas de boa qualidade, evidenciando a necessidade de adoção de providências perante a coordenação pedagógica no sentido de melhorar a capacidade dos alunos de odontologia da Faculdade de Odontologia de Caruaru em relação aos exames radiográficos

Clinical examination along with radiographic examination is the key in making the diagnosis in several procedures in dentistry. The periapical radiograph shows a type of radiographic examination as a method widely used in the diagnosis, which allows the professional planning of the implementation of safer treatment proservation and documentation in general. However, for a correct and safe interpretation, they are necessary standardized and quality radiographs to enable the establishment of a proper diagnosis. Taking these aspects into account, the periapical radiograph should be well handled so that we can provide details of the area imaged. Thus, this study aims to evaluate the pattern of radiographs taken at the CEO of Endodontics, Faculty of Odontology of Caruaru - PE in the period 2004 to 2007. 460 radiographs were analyzed which showed that major errors founded were: packaging (71.96%), washing (37.17%), placement of radiographic film (33.04%), oxidation (31.52%) processing errors (light and dark 23.04% 5.7%), and some others. In the end, there was a high failure rate and a minimum percentage of radiographs considered of good quality, which suggests the need for adoption of measures with the pedagogical coordination to improve the ability in radiology of the odontology students of the Faculty of Odontology of Caruaru

Evaluation of a Gafchromic EBT2 film dosimetry system for radiotherapy quality assurance.

This study examines the dosimetric accuracy of Gafchromic EBT2 model radiochromic film for use in radiotherapy quality assurance. In this study, film was scanned using an Epson Perfection V700 flatbed scanner in transmission mode at 75 DPI with the subsequent analysis performed using the red and blue colour channels and ImageJ software. Results of this study suggest that the conversion of film optical density to measured dose should, at present, utilise red channel data only, without application of a blue channel correction to the data. For the batch of film examined here, film uniformity and reproducibility appear to have improved compared with published results using older batches. The orientation of the film on the scanner and the side of the film facing the light source were found to have substantial effects on results. Based on the results of this study, it is possible to recommend the use of EBT2 film in routine quality assurance testing for radiotherapy, in situations where a dose uncertainty of up to 2.8% is acceptable.

Evaluation of EBT radiochromic film using a multiple exposure technique.

Radiochromic film is a self developing two-dimensional dosimeter system that is widely used in radiotherapy. Since its development some 40 years ago many improvements have been made; however the sensitivity can vary across the film and a non-linear dose response remains. The former can be addressed using a double exposure technique; however this technique assumes that the response is linear so that the dose distribution is incorrectly measured. We are proposing the use of two homogenous exposures; one performed prior, the other after the irradiation to be measured. In this 'multiple exposure technique' (MET), the first homogenous exposure can be used to correct for variations in response in different parts of the film, while the second homogenous exposure allows correction for non-linearity of response with dose. The MET was tested with a 60° wedged field and an Intensity Modulated Radiation Therapy fluence map produced by a computerised treatment planning system. In the wedge field measurements, the MET profile showed agreement within 0.6 cGy for 80% of the field compared to ionisation chamber dose values. A comparison of a TPS generated fluence map dose distribution with one measured using conventionally calibrated EBT, and another measured with MET calibrated EBT, showed similar agreement. The MET would be particularly useful for the assessment of highly inhomogenous dose distributions with high maximum dose such as encountered in hypofractionated radiation therapy.

Evaluation of effective energy using radiochromic film and a step-shaped aluminum filter.

Although the half-value layer (HVL) is one of the important parameters for quality assurance (QA) and quality control (QC), constant monitoring has not been performed because measurements using an ionization chamber (IC) are time-consuming and complicated. To solve these problems, a method using radiochromic film and step-shaped aluminum (Al) filters has been developed. To this end, GAFCHROMIC EBT2 dosimetry film (GAF-EBT2), which shows only slight energy dependency errors in comparison with GAFCHROMIC XR TYPE-R (GAF-R) and other radiochromic films, has been used. The measurement X-ray tube voltages were 120, 100, and 80 kV. GAF-EBT2 was scanned using a flat-bed scanner before and after exposure. To remove the non-uniformity error caused by image acquisition of the flat-bed scanner, the scanning image of the GAF-EBT2 before exposure was subtracted after exposure. HVL was evaluated using the density attenuation ratio. The effective energies obtained using HVLs of GAF-EBT2, GAF-R, and an IC dosimeter were compared. Effective energies with X-ray tube voltages of 120, 100, and 80 kV using GAF-EBT2 were 40.6, 36.0, and 32.9 keV, respectively. The difference ratios of the effective energies using GAF-EBT2 and the IC were 5.0%, 0.9%, and 2.7%, respectively. GAF-EBT2 and GAF-R proved to be capable of measuring effective energy with comparable precision. However, in HVL measurements of devices operating in the high-energy range (X-ray CT, radiotherapy machines, and so on), GAF-EBT2 was found to offer higher measurement precision than GAF-R, because it shows only a slight energy dependency.

Evaluation of radiographic image quality parameters obtained with the REX simulator.

The PTW REX phantom was used to study the radiographic image quality parameters in X-ray devices in the X-ray Diagnostics Department, as well as the system of film processing at the University Hospital of Rio de Janeiro State. X-ray devices were evaluated by performing tests on 11 screen-film combinations from X-ray devices in 3 rooms. The results showed that six film-screen combinations exhibited poor performances. For determination of air kerma output in the X-ray field, two devices presented significant variation >2 %. The grid attenuation factor in three devices had been approved, while two films were within the limits of sensitometric specifications. The modulation transfer function, which evaluates the level of image degradation, revealed that five film-screen combinations exhibited bad performance. The tests with the REX phantom revealed that the X-ray equipment and the system of processing at the University Hospital presented discrepancies in relation to the expected values, contributing to loss of quality of the radiographs.

Using precisely controlled bidirectional orthopedic forces to assess flexibility in adolescent idiopathic scoliosis: comparisons between push-traction film, supine side bending, suspension, and fulcrum bending film.

STUDY DESIGN: A prospective study. OBJECTIVE: To validate the effectiveness of push-traction film (PTF) in assessment of curve flexibility in adolescent idiopathic scoliosis. SUMMARY OF BACKGROUND DATA: There is no agreement among surgeons about the most advantageous method in flexibility evaluation of scoliosis. As all methods available provide the orthopedic force from one direction and use a single torque, it is difficult for them to achieve the postoperative correction; also they could not meet the needs for different types of curves. METHODS: Precisely controlled bidirectional (push and traction) orthopedic forces were applied for curve flexibility evaluation in 31 consecutive adolescent idiopathic scoliosis patients. The correction rate (CR) of postoperation, supine side-bending, suspension, and fulcrum bending radiographs were compared with PTF in instrumented main thoracic (MT) and thoracolumbar/lumbar curves. Correlation and linear regression analyses were also been done to find the best predictor among the four methods. RESULTS: In MT group, CR of PTF was significantly higher than that of side bending (P = 0.010) and suspension (P = 0.000) but not significantly different from that of fulcrum bending (P = 0.335). In TL/L group, CR of PTF was significantly higher than that of suspension (P = 0.000), but not significantly different from that of side bending (P = 0.681) and fulcrum bending (P = 0.382). There was no significant difference between CR of PTF and postoperation in both MT (P = 0.122) and TL/L (P = 0.068) groups. Correlation and linear regression analyses showed that PTF provided the highest correlation of the four methods, with the postoperative angle in both MT (r = 0.957) and MT/L group (r = 0.779). CONCLUSION: To our knowledge, this was the first report about using precisely controlled bidirectional correction forces for curve flexibility evaluation. Although it did not achieve the best CR among the four methods studied, correlation and regression analyses confirmed that PTF was a more stable and accurate method to predict flexibility. We believe that further exploration of a more rational push-traction force ratio would help to obtain a better flexibility.