How Much Does the Type of Tympanostomy Tube Matter? A Utility-Based Markov Decision Analysis

Abstract

Objectives:

Different types of tympanostomy tubes (TT) are available to the otolaryngologist with relative advantages and disadvantages. The objectives of this study are: (1) Use a utility-based Markov Decision Analysis model to compare outcomes of short-term grommet tubes, “intermediate” type tubes (Triune, Grace Medical, USA), and “permanent” T-Tubes. (2) Use sensitivity analysis to determine the most important factors influencing outcomes with one type of TT versus another.

Methods:

A Markov cohort decision analysis model was created using computer software (Treeage Software, Inc. USA) comparing the 3 types of TT. Published data were used to determine key baseline model parameters. The model featured potential complications including eardrum perforation, early TT extrusion, and the need for possible repeat TT placement after extrusion. Outcomes were quantified using a 0.95 (one procedure, full recovery) to 0.6 (failed myringoplasty) utility scale. Utility values were discounted over time to incorporate real life inconvenience. Statistical analysis included simple descriptive statistics and contingency tables.

Results:

The intermediate TT accumulated superior total utility in 2-, 4-, and 6-year models (2.48, 3.96, and 5.27 total utility) compared with grommets (2.32,3.82,5.18) and T-tubes (2.42, 3.86, 5.18). Examining a hypothetical 3000 child cohort, T-tubes resulted in an increased overall perforation rate (10.5% versus 2.0%, P < .001 chi-squared). Sensitivity analysis indicated that the rate of repeat TT placement and the inconvenience utility discount factor over time were the driving factors of the model.

Conclusions:

The intermediate TT may produce favorable outcomes as it combines a balance of a lower perforation rate than T-tubes and a longer period of ventilation than grommet tubes.