The Area under the Main Sequence as an Alternative Method to Measure Saccadic Dynamics.

SIGNIFICANCE: This study shows that the area under the main sequence (MSAREA) is a valid alternative to the standard peak-velocity main sequence in measuring saccadic dynamics. A one-parameter area model, MSAREA = GPW = 1.55 × SACSIZE, with SACSIZE as the size of the saccade, 1.55 as a power factor, and GPW = 1.55 as a gain parameter, is presented. PURPOSE: SACPEAK = Vmax × (1 - e) is the traditional model used to describe the saccadic main sequence, the relationship between the size of the movement and its peak velocity (SACPEAK). In the previous article, we have shown that there is a strong linear correlation between the two parameters Vmax and SAT, which severely affects the model's clinical applicability. The purpose of this study is to see if, by using the MSAREA as an alternative approach, we can overcome the limitations of the traditional model. METHODS: Participants and main sequence data are the same as the previous study. A trapezoidal integration was used to estimate the MSAREAs as a function of SACSIZE. RESULTS: A two-parameter area model was computed to determine the range of variability of its parameters and R values. These were then used as reference values in the search for one-parameter alternatives. The one-parameter model MSAREA = GPW = 1.55 × SACSIZE performed well for all data sets. We tested its validity by performing a comparison with other one-parameter area models. CONCLUSIONS: Area models are superior to peak-velocity models in terms of R and stability and can be reduced to robust one-parameter expressions with only limited degradation in R. This not only greatly simplifies the determination if a set is inside or outside a reference population but also allows for direct comparisons between sets, with the saccadic dynamics expressed by a simple linear gain factor (GPW = 1.55).

Factors influencing the use of outcome measures in physical therapy practice.

Use of outcome measures in physical therapy practice is central to evaluating the effectiveness of treatment interventions, providing accountability and addressing quality of physical therapy programs. There is limited discussion on barriers and facilitators to using outcome measures in physical therapy practice. The purpose of this study was to identify factors that influence a physical therapist when deciding to use outcome measures in clinical practice. Participants were 21 physical therapists, seven each from skilled nursing facilities, outpatient clinics, and inpatient rehabilitation facilities. A grounded theory approach was used for interview and data collection. Common themes were determined from the data and a theory developed to explain the rationale behind physical therapists' decisions to use or not use outcome measures in clinical practice. Three overlapping themes related to (1) concepts of time, (2) knowledge, and (3) facility culture were indentified as factors influencing the use of outcome measures. A fourth encompassing theme, professionalism, identified the value placed on the use of outcome measures in practice. Data revealed that therapists require more information on the outcome measures available, and this information needs to be easily accessible within the workplace. Therapists value information generated by using outcome measures in the clinical setting, but need information on what measures are available and psychometric properties. Information must be easily accessible and measures easy to use. Newer graduates and recent learners have a foundation in the use of outcome measures, but more needs to be done in the clinic and through continuing education to promote increased use and understanding.