The shortage of a competent public health workforce has been recognized as a major problem by the World Health Assembly. WHO has claimed an urgent need for action (WHO, 2007) . One of the well-identified causes of such deficient public health competencies is the lack of adequate training, i.e. training that takes into account the health needs of the population (WHO, 2006; HRSA, 2005) as well as training that integrates effective educational strategies (Guilbert, 1999; Pruitt & Epping-Jordan, 2005) . Indeed, educational experts have stressed that relevancy of a public health training program, i.e. its capacity to address priority health needs of the population, is a key factor to any training program aiming at having some impact on public health problems the communities are facing (Institute of Medicine of the National Academies, 2003; Petrakova & Sadana, 2007 ), university-based programs often being excessively academically-oriented (EU Education and Culture DG, 2015) .
In the late 1980s a study of the University of Geneva exploring the needs for competencies in the public health sector in French-speaking Switzerland (Chastonay, Guilbert, & Rougemont, 1992) concluded that it was imperative to develop an on-job public health training program of master’s level that would be fully community-oriented adopting a partially community-project-based learning strategy (Chastonay, Durieux-Paillard, Guilbert et al., 1994) , thus respecting the recommendations of modern andragogy (Knowles, Holton, & Swanson, 2015) , as well as possibly impacting concrete public health outcomes (Jacobs, Jones, Gabella et al., 2012) . The development of such a program was at that time possible due to the policy of the Swiss Federal Government allocating extra funding to promote continuing education, the concept behind being “to promote acquisition of new professional competencies and to favor job-mobility” in a rapid changing work environment, a policy still in force (CH-EDK, 2013) . Universities were eligible to such funding.
We present some evaluation data of the 25 years experience of a Master in Public Health program at the University of Geneva, an on-job program heavily project-centered and problem-oriented and discuss some successes, challenges, limitations and failures of such a program.
2.1. Brief Description of the Program
The Geneva University Master Program in Public Health (Master of Advanced Studies in Public Health according to the Bologna Protocol (European Commission (2015) is an on job part-time three-year public health training program. Students are mostly mid-level health professionals working either in health care or in public health institutions (physicians, nurses, mid-wives, economists, biologists, sociologists, lawyers, etc.) from French-speaking Switzerland and nearby France and Italy with up to 20% of students from French-speaking African countries. Classes are limited to 5 - 15 students a year (Chastonay, Durieux- Paillard, Guilbert et al., 1994) . The program is heavily based on the development and implementation of public health projects relevant to the students’ employers/communities and on problem-solving case studies in-group work. More traditional teaching like lectures are limited to basic public health topics/discip- lines/methods. Special attention is given to “sharing” the individual experience and expertise of and with students (Chastonay, Papart, Durieux- Paillard, 1997) .
2.2. Evaluation Procedures
2.2.1. Target Population
The target population was the graduates of 25 successive cohorts of students from the beginning of the program in 1990 to present (n: 166 graduates). As mentioned above the students are mostly mid-level health professionals with at least 5 years of professional experience working either in health care or in public health institutions (physicians, nurses, mid-wives, economists, biologists, sociologists, lawyers, etc.). The male/female ratio is 0.9. The age range was 26 - 51 years, with a mean age of 37 years.
First, achievement of learning objectives was investigated through content analysis of students’ reports on personal projects in relation to pre-defined learning objectives (Hsieh & Shannon, 2005) , through problem-solving final examinations and on a self-reported progress on a professional profile, profile defined during the planning phase of the program on the basis of international recommendations and local studies among senior public health professionals and state medical officers (Chastonay, Guilbert, & Rougemont, 1992; Public Health Foundation, 2010) . Second, possible public health impact was estimated through implemented project analysis (Habicht, Victora, & Vaughan, 1999) . Third, yearly satisfaction inquiries were done with the successive cohorts using the SWOT grid (strengths, weaknesses, opportunities and threats) (Sorensen & Vidal, 1999) to investigate the students’ perception of the program: the SWOT grid method implies that students list the main strengths and weaknesses of the program, as well opportunities and threats the program faces on the long run. The listing was completed individually and later discussed among members of the respective cohorts.
3.1. Learning Evaluation
Examples of learning objectives in the context of developed public health projects by students are given in Table 1. The project implementation allowed achieving learning objectives while having some community impact.
Examples of certifying exams are given in Table 2, indirectly illustrating the
Table 1. Learning evaluation: Examples learning objectives for given students through project planning and implementation in order to solve a “real-life” problem.
Table 2. Learning evaluation: examples of certifying exams at the end of the program (72-hour group work).
kind of competencies students had to acquire during the curriculum, i.e. practical public health competencies.
Table 3 illustrates the self-perceived progress in various public health competencies (professional profile) achieved by the end of the program by 5 consecutive cohorts: globally progress is achieved, yet at various levels depending the specific tasks. For example, at the beginning of their curriculum only 16.6% of students considered themselves competent or highly competent for the specific task “Establish the health profile of the population at local and national levels”; by the end the percentage was up to 75%. Best acquired competencies as stated by 91.6 % were “Communicate with the population, with health authorities, with NGOs”, “Collaborate with health professionals and coordinate common actions”, “Develop, implement and evaluate training programs for health professionals”. Less acquired competencies included “Organize an information system to collect health data” (62.5%) and “Analyze the financial impact of health promotion programs” (58.3%).
3.2. Impact Evaluation
Institutional and community impacts may be linked to the implementation of specific projects by students. Table 4 gives some examples of projects developed and implemented during the training by students and it shows the estimated related impact either at the institutional level or at community level. Each student eventually implemented at least one project over his training time, often small grass-root projects limited to a specific setting, but sometimes also quite large projects as shown in Table 4.
3.3. Satisfaction Evaluation
Satisfaction evaluation allowed identifying strengths and weaknesses of the program
Table 3. Degree of self-perceived competency in public health tasks at the beginning and at the end of the program (5 consecutive cohorts n: 48) (on a 4-point scale 1 no competency, 2 basic competency, 3 competent, 4 highly competent).
Table 4. Impact evaluation: Examples of projects implemented by students and estimated/observed results on institutional or community levels.
as perceived by the students. Table 5 shows overall perception of students when data of successive years were aggregated. “Group dynamics” appears as a strong point, as well as “student-colleagues’ public health expertise”. “Networking” and “community-project conception/implementation” are other strong elements of the program. Weaknesses put forward are namely “limited interaction with students’ employers” and “little visibility of the program at national and international levels”. Interesting named potentials are “intercultural exchanges among students from different cultural backgrounds” and “multi-professional classes”. Obstacles mentioned are “time constraints” or “additional workload”.
Our program has adopted the main principles of andragogy (Knowles, Holton, & Swanson, 2015) , therefore being very problem-solving oriented as has been recommended out of educational efficacy in the WHO Educational Handbook for Health Personnel (Guilbert, 1999) . Furthermore the program is markedly project-based learning oriented, possibly enhancing its public health relevancy (Guilbert, 1999; HCRC, 2000) as one could consider looking at the projects
Table 5. Students’ satisfaction monitored through the SWOT technique: most frequently mentioned points in a yearly survey (pooled data of 465 questionnaires corresponding to 166 students) ranked from 1 to 4.
developed by students of the program and ultimately implemented in their employing institutions or in their respective communities or even contributing to efficient public health workforce, an ever needed “species” as mentioned by the Institute of Medicine (Institute of Medicine of the National Academies, 2003) .
Defining learning objectives allowing the acquisition of basic public health competencies through project planning and implementation was a globally appreciated exercise for most students, though often also a somewhat difficult endeavor as has been reported in the literature (Edutechwiki, 2009) . For the students it meant actively shaping their education, thus becoming the architect of their training as recommended by educational experts from WHO (Guilbert, 1999) and doing it in a public health perspective, i.e. proposing projects relevant to their community and/or institution. As shown in Table 1 the acquisition of specific public health skills was possible through project planning and implementing, a acquisition mechanism often reported by project learning and learning by doing supporters/experts (Thomas, 2000; Mergendoller & Thomas, 2003) . Yet, in our program the progress in various competencies, as shown in Table 3, was also facilitated through more traditional problem-solving group work, i.e. realizing in class assignments, as the ones shown in Table 2. Such group work also facilitated interaction among students and exchange of experiences, a hallmark of adult learning (Knowles, Holton, & Swanson, 2015) .
From the students’ perspective most satisfying elements were the “development of a functioning professional network”, the “implementation of public health projects in the community”, the “boosting of professional carrier”, the “acquisition of specific public health tools”, the “increased awareness of the need for life-long learning”.
Over time the development of a functioning network became a primary objective of the program for the coordinating staff because of its importance in a public health action perspective. Indeed, functioning networks have been stressed as a key factor for an efficient public health policy (Luke & Harris, 2007) : e.g. network strategies to advance public health for Europe have been proposed (Semenza, Apfle, Rose, & Giesecke, 2008) . Though public health networks have primary been used to control infectious diseases, their importance has been demonstrated in different contexts: diffusion of information and innovations, influence on personal health behaviors, role of social support, influence on organization of the health sector (Valente & Davis, 1999; Leischow & Milstein, 2006; Valente, Gallaher, & Mouttapa, 2004) .
In our project centered and problem-based on-job curriculum some major challenges had to be faced by students (and staff):
- A major challenge for most of our students has been time constraints related to supplementary workload due to the program requirements. Indeed, our program is an on-job program and our students are mainly professionals in their late thirties-early forties. This means managing educational objectives and job requirements, family obligations and community involvement. Of course one could also consider that this time management challenge is a specific skill useful for any professional as has been suggested by some authors (Trueman & Hartley, 1996) .
- A second challenge for many students was to acquire new competencies in exploring new public health challenges and new public health tools, because of time constraints or out of commodity, and somehow favored by our individual and project-based educational approach, though our list of public health competencies served as a reassuring/stressing framework. Yet professional competencies required in public health are not a static set in an ever-changing world facing ever-changing health problems (Pruitt & Epping-Jordan, 2005) .
- Another challenge was handling the “interface between educational objectives of the students and professional expectations of the employers”: this implies flexibility from the employers and from the employees (our students), ultimately requesting some negotiating skills as well as adapting and transformative learning (Harvey, 2000) . However some concrete support from the employer is needed, be it financial or organizational: this definitively strengthens the student-employee’s motivation (Schuller, Raffe, & Clark, 1997) .
Some built-in bias might exist in our report. Indeed especially the students’ self-reported perceptions of the program might be considered as quite subjective. Yet our observations might well suggest that a community-oriented, project-based, on-job public health program possibly gives students competencies that enable them to implement projects that might ultimately improve the health of the populations they are in charge of. Another limit of our approach is the non-systematic data collection on specific outcomes, though we were able to estimate some community impact due to the project-based approach the program is heavily built on.
Twenty-five years of a community-oriented and project-based public health training program have strengthened ties between the University and the health authorities, the public health actors as well as triggered many prevention and health promotion projects in the communities. Yet it has not triggered a drastic change in the health sector that would have put on top of the agenda disease prevention and health promotion.
 Chastonay, P., Durieux-Paillard, S., Guilbert, J. J., Brenner, E., & Rougemont, A. (1994). A Learner-Centered Curriculum in Public Health at the University of Geneva. Teaching & Learning in Medicine, 6, 75-85.
 Chastonay, P., Guilbert, J. J., & Rougemont, A. (1992). Les besoins institutionnels en matière de santé publique: Une enquête dans trois cantons romands et au Tessin. Cahiers Médico-Sociaux, 36, 45-53.
 Chastonay, P., Papart, J. P., Durieux-Paillard, S., Etter, J. F., Etienne, Y., Barazzoni, F. et al. (1997). Stratégies et outils pédagogiques dans le cadre d’un Diplome de santé publique. Sozialund Praventivmedizin, 42, 55-65.
 EU Education and Culture DG (2015). Tuning Educational Structures in Europe. Approaches to Teaching, Learning and Assessment in Competences Based Degree Programmes.
 Habicht, J. P., Victora, C. G., & Vaughan, J. P. (1999). Evaluation Designs for Adequacy, Plausibility and Probability of Public Health Program. International Journal of Epidemiology, 28, 10-18.
 Institute of Medicine of the National Academies (2003). Who Will Keep the Public Healthy: Educating Public Health Professionals for the 21st Century?
 Jacobs, J. A., Jones, E., Gabella, B. A., Spring, B., & Brownson, R. C. (2012). Tools for Implementing an Evidence-Based Approach in Public Health Practice. Preventing Chronic Disease, 9, Article ID: 110324.
 Luke, D. A., & Harris, J. K. (2007). Network Analysis in Public Health: History, Methods and Applications. Annual Review of Public Health, 28, 69-93.
 Petrakova, A., & Sadana, R. (2007). Problems and Progress in Public Health Education. Bulletin of WHO, 85, 901-980.
 Schuller, T., Raffe, D., & Clark, I. (1997). Part Time Higher Education and the Student Employer Relationship. Journal of Education and Work, 10, 225-236.
 Semenza, J. C., Apfel, F., Rose, T., & Giesecke, J. (2008). A Network Strategy to Advance Public Health in Europe. European Journal of Public Health, 18, 441-447.
 Sorensen, L., & Vidal, R. V. (1999). Getting an Overview with SWOT. Danish National Research Database, Technical University of Denmark.
 Trueman, M., & Hartley, J. (1996). A Comparison between Time-Management Skills and Academic Performance of Mature and Traditional-Entry University Students. Higher Education, 32, 199-215.
 Valente, T. W., Gallaher, P., & Mouttapa, M. (2004). Using Social Network to Understand and Prevent Substance Use: An Interdisciplinary Perspective. Substance Use & Misuse, 39, 1685-1712.