This study is an extensive attempt at applying the cohort approach in projecting future supply of physicians in Thailand with a 1% annual loss rate. This assumes that the physician population is in an expanding state despite the increase in the annual loss rate in comparison to that found in the previous study by Suwannakij et al. in 1996. Given that the assumptions are valid, especially the 1% annual loss rate, the fine-tuning of the Medical Council dataset on the stock of physicians, the future production capacities of medical schools, and the rate of graduates gaining licences, the projected supplies will be able to match the national goals of one doctor per 1,500 population as proposed by the 7th National Conference on Medical Education by 2020, and one per 1,800 proposed by the MoPH by 2016.
A key factor that has kept the supply of physicians in an expanding state has been the rapid increase in physician production over the past two decades. This has been the result of a set of policies aimed at expanding physician supply, e.g. establishing a number of new public medical schools, recruiting a greater number of students into medical schools, in particular those in remote areas, through various modes of admission. The Collaborative Project to Increase Rural Doctors (CPIRD), launched by the MoPH in 1994, is a good example of these policies. It has enrolled around 300 students per annum from rural backgrounds, with a mandate that these students need to serve their hometown upon graduation . The project also plans to increase its production levels to produce 3,807 graduates between 2009 and 2019.
In carrying out this study, several limitations were addressed with a rigorous evidence-based methodology. However, several remaining limitations were identified as follows:
The assumption that the cohort age-specific loss rate will remain unchanged in the future may not hold true , because other elements of the contextual environment may change rapidly, such as, labour market dynamics. Since the recovery from the economic crisis in early 2000, the private sector’s demand for physicians has grown significantly and may cause a brain drain of physicians from the public sector . In the context of the upcoming 2015 inauguration of the ASEAN Economic Community , the relaxation of medical council requirements on licensing may increase the number of foreign graduates practising in Thailand; meanwhile, licensing relaxation in recipient countries may stimulate outward migration of Thai physicians to practise abroad. Increased job opportunities in other economic sectors may also stimulate losses from professional practice.
A significant change in the demographics of physicians, specifically the great increase in female students enrolling in medical schools, may affect physicians’ career patterns and as such the loss rate will need further examination. The evidence from a survey of new medical graduates in 2011, by the International Health Policy Program, revealed that only 40% of new graduates were male . This is in contrast to the current gender ratio of overall physicians in Thailand in which around two-thirds of physicians are male .
The cleaning of the Thai Medical Council’s dataset on the stock of physicians relied on the 2010 and 2011 surveys, which concluded that 83% of total registered physicians were active in clinical practice; the surveys may have had numerous limitations, such as the representativeness of respondents to the overall physician population, and neither took into account the potential for a return to practice after a career break. This inevitably has an effect on the accuracy of this data.
Focusing on the national average obscures the issue of the sub-national distribution of physicians, for which parallel policies should be in place to address imbalances. This study quantifies the future supply of physicians; however, quality, in terms of clinical competency, communication skills, human interaction, social skills and attitudes and capacity to conduct ‘interprofessional teamwork’, is an equally important factor determining productivity and outcomes. This study indicates that, if the given assumptions hold, current production capacity is adequate to meet the national goals of physician density of 1:1,800 by 2016 and 1:1,500 by 2020, but policy makers should not be complacent as a result of these findings. This supply of physicians, if achieved, does not fully ensure that there will be adequate physicians to respond to the health needs of the population. Maldistribution is still a major policy concern; in 2005, physician density was around 1:800 in Bangkok, almost nine times as high as the density in the Northeast where it was 1:7,000. Almost one quarter of the total number of physicians was employed in the private sector  and this trend is increasing .
It should be noted that the results of this study will yield greater benefits if integrated into the production and employment planning of other health professions e.g. nurses, dentists, pharmacists, and also medical specialities. Elaborating on the findings of the study, by taking into account the production planning of other professions in concordance with the population’s health needs, may be useful for policy implementation in an effective manner.
Evidence-based health workforce policy and planning requires more accurate data on both stock and flow of physicians. While there has previously been ad hoc physician cohort data collection undertaken, there is a need for regular, routine and integrated collection of physician data by cohort, as part of a strengthening of the whole human resources for health information system. This would improve on the routine registration dataset collected by the Medical Council, ensure greater provision of information to the public, and reflect professional employment dynamics, in particular, losses from the profession and from clinical practice. Ad hoc surveys usually suffer from poor response rates and the non-representativeness of respondents. A 20-year Thai nurse cohort study , launched in 2010, provides useful information on the life dynamics of Thai nurses, it monitors the loss rate and assesses the duration of the nursing career – one of the vital parameters in health workforce planning. Lessons from the nurse cohort study would be useful for establishing a physician cohort study in Thailand.