Can a Brief Training Session Prepare Physician Sonographers of Differing Experience to Measure the Ischiofemoral Space? A Reliability Study.

OBJECTIVE

The primary aim of this study was to determine the inter- and intrarater reliability of ultrasound (US) measurements of the ischiofemoral space (IFS) following a brief training session. A secondary aim was to determine if reliability correlated with sonographer experience.

DESIGN

Prospective cohort study.

SETTING

Physical medicine and rehabilitation department within a tertiary care institution.

PARTICIPANTS

Seven male and 3 female individuals were recruited to serve as models. Nine physician sonographers (3 postgraduate year [PGY]-2 residents, 3 PGY-4 residents, 3 physicians) were recruited to serve as sonographers.

METHODS OR INTERVENTIONS

Sonographers received a 15-minute educational session on identifying the IFS with US, followed by 20 minutes of practice. Models were then placed in a prone position and secured to prevent hip movement. All operators measured bilateral IFSs in each model twice with a washout period between measurements. Operators were blinded to all measurements.

MAIN OUTCOME MEASURES

Primary outcomes were inter- and intrarater reliability interclass coefficients (ICCs) of IFS measurements among the groups with different levels of US experience. Secondary outcomes included comparisons of inter- and intrarater reliability ICCs of IFS measurements between groups, and the difference of mean IFS measurements between groups.

RESULTS

Intrarater reliability ICCs were 0.829, 0.680, and 0.596 for physician, PGY-4, and PGY-2 groups, respectively. Interrater reliability ICCs were 0.722, 0.427, and 0.558 for physician, PGY-4, and PGY-2 groups, respectively. No statistically significant differences in reliability were identified between groups. Mean IFS measurements were 31.2, 33.4, and 34.0 mm for physician, PGY-4, and PGY-2 groups, respectively. Physician measurements were significantly smaller than the PGY-4 and PGY-2 measurements (P < .049 and P < .01).

CONCLUSIONS

Following a brief training session, experienced sonographers demonstrated excellent IFS measurement intrarater reliability, whereas PGY-4 and PGY-2 sonographers demonstrated fair intrarater reliability. All sonographers demonstrated fair interrater reliability.

LEVEL OF EVIDENCE

II.