Ahmad et al. BMC Public Health 2012, 12:132 http://www.biomedcentral.com/1471-2458/12/132 frequently than females [20]. Patient loss in SHC was twice as high as loss in MHC. Several studies have sug- gested that the quality of services is a common reason for defaulting before initiating treatment [20-22]. One possible explanation in our study could be the substan- tially longer duration of the diagnostic work-up or inadequate information provided to the patients in SHC. A study in a similar setting in Java indicated that only 20% of the nurses in health centres provide adequate information to TB suspects regarding sputum samples [23]. Because patients were not traced, we do not know if they felt better or consulted other health services. As the subsequent consultations, if any, were all self-refer- ral, we did not consider the subsequent consultation as part of the TB diagnostic work-up under study. A possi- bility of self-selection (i.e. patients with minor symptoms went to the SHC, whereas more severe patients pre- ferred to go to the MHC or lung clinics) exists, and the latter group may be more motivated to adhere to health providers’ orders. The diagnostic delays were significantly longer in SHC and MHC compared to lung clinics, most likely due to the diagnostic capacity of the centre, which influences the timing of different examinations. All facilities and skills required to perform a smear-negative TB diagnosis are readily available in lung clinics, whereas SHC need to send the sputum smears to the referral MHC and wait for the report of the results. Also, in the case of chest radiography by the health centres, most patients need to be referred to higher-level hospitals or lung clinics, which causes further delay. Furthermore, lung clinics tend to perform multiple examinations at the same contact. Although this practice is not in line with the national diagnostic algorithm, it significantly reduces the duration of a diagnostic work-up. All diagnoses at the lung clinics were made without complying with the national diagnostic algorithm, but this considerably reduced the diagnostic delay and pre- vented patient loss. Getahun et al. argued that the health service delay introduced by applying the TB diagnostic algorithm in a linear fashion could be life threatening, particularly among HIV-positive patients, as it needs 11- 34 days to establish the diagnosis of smear-negative pul- monary TB under the most optimistic scenarios [7]. An additional guideline to expedite the TB diagnosis pro- cess was published specifically for HIV-positive smear- negative TB suspects [6]. The Stop TB Partnership has endorsed an international standard of tuberculosis care (ISTC) since 2006 [24]. The standardised diagnostic algorithms are developed to improve the sensitivity and specificity of TB diagnosis among health providers within the TB control programme, particularly in pri- mary health centres, whereas the purpose of the ISTC is to provide guidelines that are more suitable for all Page 5 of 6 practitioners, particularly those working in the private sector, and allow some degree of flexibility. The ISTC recommends sputum smear examination of all patients suspected of having pulmonary TB and all persons with chest radiographic findings suggestive of TB. The ISTC also acknowledges that many providers do not adhere to the TB diagnostic algorithm in a sequential fashion, and that the approach outlined in the algorithm may be quite costly to the patient as it may take several visits to complete the diagnostic work-up, deterring her/him from continuing with the diagnostic evaluation. There- fore, the ISTC recommends that the application of such an algorithm be done in a flexible manner [25]. Our study found that all TB patients who completed the diagnostic work-up in lung clinics or health centres underwent sputum examination at some point during their diagnostic work-up, which still conforms to the ISTC recommendations. Considering the diagnostic capacity of lung clinics, applying the ISTC is more suita- ble than following the standardised national TB diagnos- tic algorithm. A recent study also suggested that the performance of the WHO-based diagnostic algorithm for HIV-negative TB suspects is far from optimal [12]. Another study among HIV-positive patients also sug- gested that chest radiography is the best next step after sputum examination [9]. Clearly, the Indonesia national TB programme (NTP) needs to re-evaluate the current diagnostic algorithm and policy, taking into account possible scenarios at different levels of care, new evi- dence, and recent international policy recommendations. The high rate of patients lost in health centres requires special attention. Improving service quality through better communication with patients may be the answer. However, Khan et al. reported that, even when patients were counselled, the rate of patient loss during diagnostic work-up was not reduced [20]. Faster diag- nostic technology may be a better answer. The WHO recently endorsed a new rapid molecular test for TB diagnosis following a successful evaluation in low- income countries [26,27]. The test provides a sensitivity comparable to culture but with results in less than 2 hours. However, considerable resources need to be invested and much time will elapse before this new method will be generally implemented in Indonesia. Therefore, improving the quality of service, implement- ing patient tracing, offering a diversified national algo- rithm, and ensuring better programme supervision may be the best options at the moment. Conclusions We conclude that the implementation of the diagnostic work-ups in lung clinics, and to some degree in health centres, does not conform to the national TB diagnostic algorithm, but it does conform to the ISTC. A need