Pulmonary TB is curable when presently available regimens are given to adherent patients under study conditions. Studies show that DOT i.e., a programme in which health care personnel witness patients taking all prescribed TB treatment to be more effective than traditional therapy in which prescribed medications are self-administered by the patients. It reduces the prevalence of chronic bacillary cases, relapse rates, incidence of primary, acquired and Multi Drug Resistant TB. Treatment completion and compliance rates are higher with DOT. This study compares the cost of TB treatment in DOT (it is not widely used; it is perceived to be too expensive) to the traditional therapy. The objective of the study was to directly measure the cost of TB treatment under actual programme conditions. The cost of staff salary, laboratory, outreach, medication and hospitalization were included in the measurement.

The study was a retrospective economic evaluation of all cases reported to the Tarrant County Texas Health Department, USA. The health department serves about 1 million people of greater Fort Worth metropolitan area. The patients who were culture positive, had no history of previous treatment and patients actually managed by traditional or observed therapy were eligible for intake; legally quarantined, lost to therapy, dying from other diseases, were not included for the cost analysis. Eligible patients presenting between Jan 1980 and Dec 1985 were included in the traditional group. Patient treatment costs were followed through 31st Dec 1987, while in the DOT group patients between Jan 1987 and 31st Dec 1992 were included and treatment costs were followed through 31st Dec 1994. Nearly all the patients in either group received their prescribed therapy. Cost estimates were characterized by a cost parameter and a unit rate with cost being determined from the products of the two. Cost parameters describe different elements of treatment i.e., number of X-rays, days hospitalized, physician care time, etc., and are independent of cost which provides a base for comparing the relative costs of each program. Unit rates reflect 1995 pricing for labour, services and materials and representative of costs in Tarrant County Texas. In-patient cost was determined as $600 per day for days hospitalized for TB, out-patient cost parameters included personnel service and travel time, travel mileage, number of laboratory tests, number of X-rays done and medication prescribed.

The Physicians treating TB have three out-patient management options, traditional therapy and universal or selective DOT. The selective DOT suffers from the same flaws as traditional therapy specially the inability to predict, identify and measure non-adherence.

The authors feel that out-patient management with universal DOT should be the standard public health treatment protocol, because it is both more effective and less expensive. A total of 659 patients were studied which included 257 traditional group and 402 in DOT group. The data shows that the treatment cost for traditional therapy is significantly higher ($27630 v/s $11260, P < 0.001). Out patient cost was significantly higher for patients treated with traditional therapy ($2920 v/s $2220) although personnel cost was greater for DOT group. Hospital costs were higher for patients treated with traditional group ($24710 v/s $9040, P < 0.001). The average cost of treatment failures was $94520 in the traditional group and $54350 in the observed group. Relapse or acquired resistance occurred in 10.9% of patients and accounted for 35.7% of the cost with traditional therapy as compared to 1.2% of patient and 6.0% of cost with observed therapy.