Table 2.

Calculation of Quality-Adjusted Life-Days Lost in Event Pathways for Decision Model of Treatment Strategies for Acute Otitis Media

Pathway	A Days of AOM*	B Days of Treatment Success*	C Days of Treatment Failure*	D Days of GI Adverse Effects*†	E Days of Rash*‡	Total QALDs Lost§ (95% CI)
Resolution with observation	2.7 × 0.79 = 2.1330	27.3 × 0.96 = 26.2080	0	0	0	1.6590 (0.7686–2.3583)
Clinical failure	2.7 × 0.79 = 2.1330	20.062 × 0.96 = 19.2595	7 × 0.72 = 5.0400	0.198 × 0.7 = 0.1386	0.04 × 0.77 = 0.0308	3.3981 (2.2898–4.5063)
Resolution with amoxicillin	2.7 × 0.79 = 2.1330	27.062 × 0.96 = 25.9795	0	0.198 × 0.7 = 0.1386	0.04 × 0.77 = 0.0308	1.7181 (1.0018–2.4344)
Clinical failure with amoxicillin	2.7 × 0.79 = 2.1330	19.824 × 0.96 = 19.0310	7 × 0.72 = 5.0400	0.396 × 0.7 = 0.2772	0.08 × 0.77 = 0.0616	3.4572 (2.3319–4.5824)

AOM = acute otitis media; GI = gastrointestinal; QALDs = quality-adjusted life-days; CI = confidence interval.

Notes: Clinical failure = continuation of symptoms after 2.7 days of observation and subsequent resolution with 7 to 10 days of amoxicillin. Clinical failure with amoxicillin = continuation of symptoms after 2.7 days of amoxicillin and subsequent resolution with 10 days of amoxicillin-clavulanate.

* Baseline utilities were used: 0.79 utility per day for days of AOM; 0.96 for days of treatment success, 0.72 for days of treatment failure, 0.70 for days of GI adverse effects, and 0.77 for days of rash.

† Children receiving amoxicillin had a 9.9% chance of having 2 days of GI adverse effects. Children receiving amoxicillin and then amoxicillin-clavulanate had a 9.9% chance of having 4 days of GI adverse effects.

‡ Children receiving amoxicillin had a 2% chance of having 2 days of rash. Children receiving amoxicillin and then amoxicillin-clavulanate had a 2% chance of having 4 days of rash.

§ QALDs lost were calculated by subtracting the sum of columns A through E from the study time frame of 30 days.