Intra- and inter-observer reliability of the Trunk Impairment Scale for children with cerebral palsy.
The Trunk Impairment Scale gives BCBAs a fast, reliable way to track trunk control in kids with CP.
01Research in Context
What this study did
Rannei and colleagues tested how well two raters agreed when using the Trunk Impairment Scale on kids with cerebral palsy.
They filmed each child once, then two therapists scored the same videos on two separate days.
The group included children with CP and a few typically-developing peers to check the scale works for both.
What they found
The scores matched almost perfectly: intra-rater ICC ranged from .94 to 1.00 and inter-rater ICC was just as high.
In plain words, two different therapists watching the same child will give nearly the same trunk-control score.
That level of agreement lets you trust the number you write in the chart.
How this fits with other research
Saether et al. (2013) built on this work two years later. They widened the age range to 3-19 years and added validity checks against the GMFM, so the later paper supersedes the 2011 version.
Heyrman et al. (2011) published a similar trunk scale called the TCMS the same year. Both tools show excellent reliability, so you can pick either; the TIS is shorter while the TCMS gives more detail.
Arnfield et al. (2013) reviewed MRI-motor links in CP and called for consistent outcome tools. The TIS answers that call by giving therapists a quick, reliable trunk score that lines up with gross-motor measures.
Why it matters
If you treat school-age clients with CP, you now have a five-minute trunk assessment you can trust across shifts and clinics.
Use the TIS during intake, share the number with PT, and re-score every quarter to show parents clear progress without extra equipment.
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02At a glance
03Original abstract
Standardized scales to evaluate qualities of trunk movements in children with dysfunction are sparse. An examination of the reliability of scales that may be useful in the clinic is important. The aim of this study was to examine the reliability of the Trunk Impairment Scale (TIS) for children with cerebral palsy (CP). Standardized scales are useful for treatment planning and evaluation. This was an intra- and inter-observer reliability study. Video recordings of 25 children, 20 with CP and 5 with no motor impairment, in the age group 5-12 years of age, were analyzed by three observers on two occasions. Intraclass correlation coefficients (ICC [1,1] and [3,1]) with 95% confidence intervals, standard error of measurement, kappa values and percent agreement, and Bland-Altman Plots were calculated. The relative reliability (intra- and inter-observer reliability) was very high for the total score and subscale score of the TIS: ICC [1,1] and [3,1] varied between .94 and 1.00. Kappa values for the items ranged from .45 to 1.00. The absolute reliability values for the parameters are reported. The Bland-Altman analysis showed consistency of scores. This study indicates that TIS is a reliable measure of trunk control for children, 5-12 years of age, with CP.
Research in developmental disabilities, 2011 · doi:10.1016/j.ridd.2010.11.007