[Examiner variability of clinical findings in patients with sleep related breathing disorders]

Clinical findings in sleep related breathing disorders (SRBD) and primary snoring are not only of diagnostic but also of therapeutic relevance because clinical findings may be used for the selection of surgical interventions such as uvulopalatopharyngoplasty (UPPP), maxillofacial surgery or radiofrequency induced surgical alternatives. We developed a standardized protocol for clinical examination of the upper airway using pictograms.

To determine the interinvestigators variability various parameters such as length of the uvula, position of tongue base, Angle-classification, webbing of posterior pillar and tonsil size were assessed by a number of residents and an assistant professor for Otorhinolaryngology and sleep medicine simultaneously.

95 patients (81 male and 14 female) with a mean age of 47.0 +/- 1.21 years, a Body-Mass-Index (BMI) of 27.2 +/- 0.46 kg/m2, and an Apnea-Hypopnea-Index (AHI) of 17.7 +/- 2.4 were examined. The appearance of the uvula has only little variations between different investigators (corr.: 0.943). The interinvestigator variability is also low for position of tongue base (corr.: 0.931) and Angle-classification (corr.: 0.893). The results of tonsil size and webbing assessment seems to have a higher variability (corr.: 0.880 and 0.693). Statistical significance for all parameters was p=<0.0001.

As to our knowledge, this is the first controlled study to record intraobserver variations of clinical findings of the upper airway. Standardized protocols are mandatory, and the variability of the measurements must be taken into account if results of different investigations must be compared or if changes after therapeutic interventions are to be investigated.