Reliability and Validity of Cervical Auscultation: A Controlled Comparison Using Video fluoroscopy

Cervical auscultation is experiencing a renaissance as an adjunct to the clinical swallowing assessment. It is a controversial technique with a small evidence base. We have aimed to establish whether cervical auscultation interpretation is based on the actual sounds heard or, in practice, influenced by information gleaned from other aspects of the clinical assessment, medical notes, or previous knowledge. We sought to determine (a) rater reliability and its impact on the clinical value of cervical auscultation and (b) how judgments compare with the “gold standard”: videofluoroscopy. Swallow sounds were computer recorded via a Littmann stethoscope. Sounds were sampled from 10 healthy control swallows with no aspiration/penetration and 10 patient swallows with aspiration/penetration, all recorded during simultaneous videofluoroscopy. The system generated sound quality similar to “live” bedside listening, a feature rarely seen in cervical auscultation studies. The 20 sound clips were classified as “normal” or “abnormal” by 19 volunteer speech–language pathologists with experience in cervical auscultation. After at least four weeks, 11 of these judges rated the sounds rerandomized on a new CD. Intrarater reliability kappa ranged from −0.12 to 0.71. Individual reliability did not correlate with years of experience, practice pattern, or frequency of use. Interrater reliability kappa = 0.17. Comparison with radiologically defined aspiration/penetration yielded 66% specificity, 62% sensitivity, and majority consensus gave 90% specificity, 80% sensitivity. There was a significant relationship between individual reliability and true positive rate (rs = 0.623, p = 0.040). The reliability of individual judges varied widely and thus, inevitably, agreement between judges was poor. Validity is dependent upon reliability: Improving the poor raters would improve the overall accuracy of this technique in predicting abnormality in swallowing. The group consensus correctly identified 17 of the 20 clips so we may speculate that the swallow sound contains audible cues that should in principle permit reliable classification.

[1]  K. Kuhlemeier,et al.  Intra- and Interrater Variation in the Evaluation of Videofluorographic Swallowing Studies , 1998, Dysphagia.

[2]  S. Langmore,et al.  Predictors of Aspiration Pneumonia: How Important Is Dysphagia? , 1998, Dysphagia.

[3]  M. Levine,et al.  Videofluoroscopic studies of swallowing dysfunction and the relative risk of pneumonia. , 2003, AJR. American journal of roentgenology.

[4]  B. Murdoch,et al.  Acoustic Signature of the Normal Swallow: Characterization by Age, Gender, and Bolus Volume , 2002, The Annals of otology, rhinology, and laryngology.

[5]  K. Kuhlemeier,et al.  The probability of correctly predicting subglottic penetration from clinical observations , 1993, Dysphagia.

[6]  H. Beckerman,et al.  Functional recovery after cardiac rehabilitation , 2002, Clinical rehabilitation.

[7]  Maria Gabriella Ceravolo,et al.  Predictive value of clinical indices in detecting aspiration in patients with neurological disorders , 1997, Journal of neurology, neurosurgery, and psychiatry.

[8]  P. Carding,et al.  Investigation and management of chronic dysphagia , 2003, BMJ : British Medical Journal.

[9]  S. Hamlet,et al.  Stethoscope acoustics and cervical auscultation of swallowing , 2004, Dysphagia.

[10]  J. Rosenbek,et al.  Inter- and Intrajudge Reliability of a Clinical Examination of Swallowing in Adults , 2000, Dysphagia.

[11]  J. Bamford,et al.  Classification and natural history of clinically identifiable subtypes of cerebral infarction , 1991, The Lancet.

[12]  G. Hankey,et al.  Initial Clinical and Demographic Predictors of Swallowing Impairment Following Acute Stroke , 2001, Dysphagia.

[13]  G. Ford,et al.  Resting Respiration in Dysphagic Patients Following Acute Stroke , 2002, Dysphagia.

[14]  R. Martino,et al.  Screening for Oropharyngeal Dysphagia in Stroke: Insufficient Evidence for Guidelines , 2000, Dysphagia.

[15]  C. M. Wiles,et al.  Inter and intra-rater reliability of cervical auscultation to detect aspiration in patients with dysphagia , 2002, Clinical rehabilitation.

[16]  R. Leonard,et al.  Timing of Events in Normal Swallowing: A Videofluoroscopic Study , 2000, Dysphagia.

[17]  Amanda Scott,et al.  A Study of Interrater Reliability when Using Videofluoroscopy as an Assessment of Swallowing , 1998, Dysphagia.

[18]  J. R. Landis,et al.  The measurement of observer agreement for categorical data. , 1977, Biometrics.

[19]  R. H. Mills,et al.  Using cervical auscultation in the clinical dysphagia examination in long-term care , 2004, Dysphagia.

[20]  Koji Takahashi,et al.  Methodology for detecting swallowing sounds , 2004, Dysphagia.

[21]  J. Liss,et al.  Interjudge agreement in videofluoroscopic studies of swallowing. , 1996, Journal of speech and hearing research.

[22]  Shaheen Hamdy,et al.  Social and Psychological Burden of Dysphagia: Its Impact on Diagnosis and Treatment , 2002, Dysphagia.