***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: In clinical measurement comparison of a new measurement technique with an established one is often needed to see whether they agree sufficiently for the new to replace the old . Such investigations are often analysed inappropriately , notably by using correlation coefficients . The use of correlation is misleading . An alternative approach , based on graphical techniques and simple calculations , is described , together with the relation between this analysis and the assessment of repeatability Background There are easily accessible tools on smartphones ( APP ) for measuring elbow range of motion ( ROM ) . The purpose of this study is to evaluate the validity of a particular APP in determining elbow ROM in comparison with the commonly used goniometer ( GON ) , surgeon estimation of range ( EST ) and measurement on X-ray ( XR ) . Methods The study included 20 patients ( 40 elbows ) .  Flexion , extension , pronation and supination were measured using three different methods : EST , GON and APP . Radiographic measurements were taken using the average humeral diaphysis axis and dorsal midthird of ulna in flexion and extension . Results The accuracy of the three different methods has been compared to GON using statistical analysis ( ANOVA and paired sample s test ) . There was no statistically significant difference for XR flexion measurement ( mean of 2.8 ° ± 1.5 ° ) . The APP overestimated flexion ( mean of 6.4 ° ± 1.0 ° ) , and EST underestimated it ( mean of − 7.9 ° ± 1.1 ° ) . For extension , the mean difference was 2.8 ° ± 0.7 ° for EST and − 26.8 ° ± 3.1 ° for XR . The APP method did not significantly differ from GON . Supination accuracy was greater with EST ( 2.7 ° ± 1.7 ° ) than with APP ( 5.9 ° ± 1.9 ° ) . There was no difference for pronation measurement with both EST and APP . Conclusions This study is the first comparing four measurement techniques of elbow ROM . Our results showed that EST was only accurate for forearm rotation . The XR scored the best for flexion but is less reliable for extension . Surprisingly , compared to GON , APP did not correlate as we expected for flexion and supination , but the other methods were also inaccurate . We found APP to be very useful to measure complete arc of motion ( difference between maximal flexion and maximal extension).Level of Evidence III , Retrospective review of a prospect i ve cohort of elbow fracture patients : Diagnostic Study Objectives The aim of our study was to develop a smartphone-aided end vertebra selection method and to investigate its effectiveness in Cobb angle measurement . Methods Twenty-nine adolescent idiopathic scoliosis patients ' pre-operative posteroanterior scoliosis radiographs were used for end vertebra selection and Cobb angle measurement by st and ard method and smartphone-aided method . Measurements were performed by 7 examiners . The intraclass correlation coefficient was used to analyze selection and measurement reliability . Summary statistics of variance calculations were used to provide 95 % prediction limits for the error in Cobb angle measurements . A paired 2-tailed t test was used to analyze end vertebra selection differences . Results Mean absolute Cobb angle difference was 3.6 ° for the manual method and 1.9 ° for the smartphone-aided method . Both intraobserver and interobserver reliability were found excellent in manual and smartphone set for Cobb angle measurement . Both intraobserver and interobserver reliability were found excellent in manual and smartphone set for end vertebra selection . But reliability values of manual set were lower than smartphone . Two observers selected significantly different end vertebra in their repeated selection s for manual method . Conclusion Smartphone-aided method for end vertebra selection and Cobb angle measurement showed excellent reliability . We can expect a reduction in measurement error rates with the widespread use of this method in clinical practice . Level of evidence Level III , Diagnostic The use of smartphones in clinical practice is steadily increasing with the availability of low cost/freely available " apps " that could be used to assess human gait . The primary aim of this manuscript is to test the concurrent validity of kinematic measures recorded by a smartphone application in comparison to a 3D motion capture system in the sagittal plane . The secondary aim was to develop a protocol for clinicians on the set up of the smartphone camera for video movement analysis . The sagittal plane knee angle was measured during heel strike and toe off events using the smart phone app and a 3D motion-capture system in 32 healthy subjects . Three trials were performed at near ( 2-m ) and far ( 4-m ) smartphone camera distances . The order of the distances was r and omized . Regression analysis was performed to estimate the height of the camera based on either the subject 's height or leg length . Absolute measurement errors were least during toe off ( 3.12 ± 5.44 degrees ) compared to heel strike ( 5.81 ± 5.26 degrees ) . There were significant ( p < 0.05 ) but moderate agreements between the application and 3D motion capture measures of knee angles . There were also no significant ( p > 0.05 ) differences between the absolute measurement errors between the two camera positions . The measurement errors averaged between 3 - 5 degrees during toe off and heel strike events of the gait cycle . The use of smartphone apps can be a useful tool in the clinic for performing gait or human movement analysis . Further studies are needed to establish the accuracy in measuring movements of the upper extremity and trunk OBJECTIVES The weight bearing lunge test is increasing being used by health care clinicians who treat lower limb and foot pathology . This measure is commonly established accurately and reliably with the use of expensive equipment . This study aims to compare the digital inclinometer with a free app , TiltMeter on an Apple iPhone . DESIGN This was an intra-rater and inter-rater reliability study . Two raters ( novice and experienced ) conducted the measurements in both a bent knee and straight leg position to determine the intra-rater and inter-rater reliability . Concurrent validity was also established . METHODS Allied health practitioners were recruited as participants from the workplace . A preconditioning stretch was conducted and the ankle range of motion was established with the weight bearing lunge test position with firstly the leg straight and secondly with the knee bent . The measurement device and each participant were r and omised during measurement . RESULTS The intra-rater reliability and inter-rater reliability for the devices and in both positions were all over ICC 0.8 except for one intra-rater measure ( Digital inclinometer , novice , ICC 0.65 ) . The inter-rater reliability between the digital inclinometer and the tilmeter was near perfect , ICC 0.96 ( CI : 0.898 - 0.983 ) ; Concurrent validity ICC between the two devices was 0.83 ( CI : -0.740 to 0.445 ) . CONCLUSIONS The use of the Tiltmeter app on the iPhone is a reliable and inexpensive tool to measure the available ankle range of motion . Health practitioners should use caution in applying these findings to other smart phone equipment if surface areas are not comparable BACKGROUND An accurate and reliable measurement of shoulder range of motion ( ROM ) is important in the evaluation of the shoulder . A smartphone digital clinometer application is a potentially simpler method for measuring shoulder ROM . The goal of this study was to establish the reliability and validity of shoulder ROM measurements among varying health care providers using a smartphone clinometer application in healthy and symptomatic adults . METHODS An attending surgeon , fellow , resident , physician assistant , and student served as examiners . Bilateral shoulders of 24 healthy subjects were included . Fifteen postoperative patients served as the symptomatic cohort . Examiners measured ROM of each shoulder , first using visual estimation and then using a goniometer and smartphone clinometer in a r and omized fashion . RESULTS The interobserver reliability among examiners showed significant correlation , with average intraclass correlation coefficient [ ICC(2,1 ) ] values of 0.61 ( estimation ) , 0.69 ( goniometer ) , and 0.80 ( smartphone ) . All 5 examiners had substantial agreement with the gold st and ard in healthy subjects , with average ICC(2,1 ) values ranging from 0.62 to 0.79 . The interobserver reliability in symptomatic patients showed significant correlation , with average ICC(2,1 ) values of 0.72 ( estimation ) , 0.79 ( goniometer ) , and 0.89 ( smartphone ) . Examiners had excellent agreement with the gold st and ard in symptomatic patients , with an average ICC(2,1 ) value of 0.98 . CONCLUSION The smartphone clinometer has excellent agreement with a goniometer-based gold st and ard for measurement of shoulder ROM in both healthy and symptomatic subjects . There is good correlation among different skill levels of providers for measurements obtained using the smartphone . A smartphone-based clinometer is a good re source for shoulder ROM measurement in both healthy subjects and symptomatic patients This study aim ed to improve clinical examination techniques by determining the reliability of different methods to evaluate forearm movements . Two methods using the iPhone ™ 5 and its gyroscope application ( alone [ I5 ] or attached to a selfie stick [ ISS ] ) were compared with two conventional measurement devices ( a plastic goniometer with a h and -held pencil [ HHP ] and a bubble goniometer [ BG ] ) to evaluate the active range of movement ( AROM ) of the wrist during pronation and supination . Two independent groups of subjects took part in this prospect i ve single-center diagnostic study : 20 healthy subjects and 20 patients . The four evaluation methods had high intra-observer consistency after three measurements ( intra-class correlation coefficient [ ICC ] [ 3 , 1 ] of 0.916 for the HHP ; 0.944 for ISS ; 0.925 for BG ; 0.933 for I5 ) and excellent inter-observer reliability ( ICC [ 2 , k ] of 0.926 for HHP ; 0.934 for ISS ; 0.899 for BG ; 0.894 for I5 ) , with an agreement of plus or minus 2 ° . When these devices are used with rigorous methodology , they are reliable for the goniometric evaluation of AROM of wrist pronation and supination ABSTRACT Purpose /hypothesis : The purpose of this study was to determine the reliability and validity of two smartphone applications : ( 1 ) GetMyROM – inclinometery-based and ( 2 ) DrGoniometry – photo-based in the measurement of active shoulder external rotation ( ER ) as compared to st and ard goniometry ( SG ) . Participants : Ninety-four Texas Woman 's University Doctor of Physical Therapy students from the School of Physical Therapy – Houston campus , were recruited to participate in this study . Material s/ methods : Two iPhone applications were compared to SG using both novice and experienced raters . Active shoulder ER range of motion was measured over two time periods in r and om order by blinded novice and experienced raters . Results : Intra-rater reliability using novice raters for the two applications ranged from an intraclass correlation coefficient ( ICC ) of 0.79 to 0.81 with SG at 0.82 . Inter-rater reliability ( novice/expert ) for the two applications ranged from an ICC of 0.92 to 0.94 with SG at 0.91 . Concurrent validity ( when compared to SG ) ranged from 0.93 to 0.94 . There were no significant differences between the novice and experienced raters . Conclusion : Both applications were found to be reliable and comparable to SG . A photo-based application potentially offers a superior method of measurement as visualizing the l and marks may be simplified in this format and it provides a record of measurement . Clinical relevance : Further study using patient population s may find the two studied applications are useful as an adjunct for clinical practice 
    Output:
    
Psychometric characteristics of the selected apps were robust , but heterogeneity of the studies did not enable comparisons between apps to identify the most valid one .