Open Access Open Badges Research

Reliability and criterion validity of two applications of the iPhone™ to measure cervical range of motion in healthy participants

Yannick Tousignant-Laflamme*, Nicolas Boutin, Alexandre M Dion and Carol-Anne Vallée

Journal of NeuroEngineering and Rehabilitation 2013, 10:69  doi:10.1186/1743-0003-10-69

PubMed Commons is an experimental system of commenting on PubMed abstracts, introduced in October 2013. Comments are displayed on the abstract page, but during the initial closed pilot, only registered users can read or post comments. Any researcher who is listed as an author of an article indexed by PubMed is entitled to participate in the pilot. If you would like to participate and need an invitation, please email, giving the PubMed ID of an article on which you are an author. For more information, see the PubMed Commons FAQ.

Application of iPhone for ROM

Pouran Faghri   (2013-08-12 15:19)  University of Connecticut

The purpose of this manuscript was to evaluate the reliability and validity of two iPhone applications aimed to measure cervical range of motion (ROM). To measure the frontal and sagittal ROM, the authors utilized the Clinometer application (Peter Breitling, Version 3.3, To measure the cervical ROM, they utilized Compass, a software application previously integrated in the iPhone. Validity was assessed against the gold standard in measuring ROM: the Cervical ROM Device (CROM).

The authors implemented a strict protocol to train the examiners in order to assure high inter-rater and intra-rater reliabilities. They also educated the two examiners to reduce error and increase validity in working with the CROM. Major differences were found between the two examiners when establishing inter-rater reliability with one examiner reaching very high ICC values (0.66-0.84) and the other one showing more inconsistent results (ICC = 0.17-0.68). The inter-rater reliability varied depending on the ROM with moderate ICC for sagittal movements and poor ICC for movements in the transverse plane. The results of criterion-related validity were in general more favorable with R-values ranging from 0.55 to 0.85. However, poor validity was reported for left rotation (R=0.38).

The one adopted in this manuscript is a very innovative approach that relies upon smartphone technology to address a common problem in rehabilitation medicine. Smartphones constitute one of the most widespread and dynamic technologies with global penetration. Currently smartphones are used for personal communication, email, Internet searches, entertainment and music. The impact of this technology in medicine is yet to be discovered.

Because of recent advances in smartphone technology and its global availability, developing applications based on smartphone technology is of great interest. While the results of the above-referenced study are promising, the following issues should be considered in the future development of medical applications of smartphone technology.

1- The development of reliable, sensitive and valid smartphone applications in the medical field should be the result of close interactions between medical professionals and smartphone application developers. Such interactions are needed to guide the development of applications suitable to assess treatment effectiveness or facilitate the clinical decision-making process.

2- In the present study, a significant amount of time was allocated to train clinical personnel in order to assure standardization of the measurement procedures and hence repeatability of the results. In the "real world", it is necessary that smartphone applications be developed so that they can be utilized without the need for dedicated, time-consuming training.

3- While the results of the study are promising and suggest that ROM can be measured reliably using a smartphone application, it must be emphasized that high-quality, evidence-based studies are needed to better understand the role of smartphone applications in rehabilitation medicine.

Pouran Faghri, MD, MS, FACSM
University of Connecticut

Competing interests



Post a comment