From a total of 424 recruits, 405 participated in this study resulting in a 95.5% response rate. The general characteristics of the study participants are presented in Table 1. A nearly equal proportion of study participants were recruited from the three ecologies. A little over half 228 (56.3%) of the health workers were females while the overwhelming majority 375(92.3%) were involved in clinical practice. Nurses constituted 152 (37.5%) while health extension workers were 97(24.0%) and physicians 85(21.0%).
A little less than half 186 (45.3%) of participants worked for less than 5 years in their professional career. More than nine in ten of the participated health care workers 367 (90.6%) indicated that they have a pre-service training on vitamin D although only 7(1.7%) of them reported an in-service training on vitamin D level measurement, diagnosis of deficiency, and management and treatment of its health consequences.
As shown in Fig. 1, the main focus areas related to vitamin D during the pre-service training were diagnosis of deficiency for 59.1% of providers, treatment of deficiency-related health conditions according to 55.3% of health care workers, food fortification on vitamin D for 48.5% respondents and food supplementation according to 51.8% of providers.
Knowledge of health care professional on adult vitamin D deficiency
As shown in Table 2, nearly a quarter of health care providers 95(23.5%) believe that dietary sources are sufficient to maintain vitamin D levels and only 11 (2.7%) think that mid-day is the best time to get vitamin D from sun exposure. However, a little more than half 207(51.1%) of the respondents revealed that 30 min is the optimal duration of sun exposure per day to get vitamin D. The proportion of health care workers who mentioned teenagers, adults and elderly people are risky population groups for vitamin D deficiency was 6 (1.5%), 6 (1.5%) and 28(6.9%), respectively. Regarding the experience of HCWs on measuring vitamin D level, identifying deficiency and management and treatment of ill health consequences only 10(2.5%), 38(9.4%), 39(9.6%) and 25(6.2%) of the health care workers felt that their competency in measuring level, diagnosing deficiency, management, and treatment of ill health consequences and all of those skills mentioned above respectively was good. Overall, only 210 (51.1%) of the study health care workers had a good knowledge score in this study.
Figure 2 showed inadequate sunlight exposure, the inadequacy of nutritional intake on food items rich in vitamin D, illnesses limiting vitamin D absorption, conditions impairing vitamin D conversion and impaired bone mineralization was reported as a cause of vitamin D deficiency by 90.1, 93.8, 58.8, 36.5 and 41.2% of the health workers included in this particular study.
On the other hand, Fig. 3 revealed that promotion of healthy bone growth, prevention of rickets, osteoporosis, and absorption of dietary calcium and phosphorous were reported as the uses of vitamin D by 97.8, 93.6, 88.9, 63.2 and 54.1% of health care workers participated in this study respectively.
The proportion of HCWs who described ill-health consequences of vitamin D such as osteoporosis, osteomalacia, hypocalcemia, hypophosphatemia and chronic illnesses was 95.6, 65.3, 64.7, 56.1, and 54.8%, respectively (Fig. 4).
When health care workers were asked about factors affecting the synthesis of vitamin D from sunlight exposure, they indicated time of day (83.2%), clothing styles (80.0%), season (75.6%), sunscreen use (69.4%), illnesses (64.9%) and pollution (61.2%) as main ones influencing syntheses (Fig. 5).
According to health workers, people who spent most of their time indoor (96.5%), cover their skin when going out (82.0%), old age persons (78.3%) and white skin people (29.4%) were the main population groups at more risk of vitamin D deficiency (Fig. 6).
The attitude of health care workers on adult vitamin D deficiency
Table 3 shows that 174(43.0%) of HCWs thought vitamin D deficiency is a public health problem and 183(45.2%) recommended universal screening to identify deficiency. However, only 16(4.0%) believe that there is an adequate laboratory investigation to diagnose vitamin D deficiency in the study area. Besides, only 45(11.1%) of study participants mentioned that vitamin D supplementation is adequate in Ethiopia. Moreover, a few 66(16.3%) thought that they are adequately aware of the prevention of vitamin D deficiency and treatment of associated diseases. On the other hand, the majority 394(97.3%) of them reported that there is a need for community sensitization on the deficiency of vitamin D. However, only 13(3.2%) of them indicated that the ministry of health or regional health bureaus has given adequate attention to the issue under the caption. Though 289(70.6%) of respondents believed that vitamin D deficiency needs an easy and less costly intervention only a few 7(1.7%) of them believed that health care providers are adequately trained on measurement of vitamin D level, diagnosis of its deficiency, and management and treatment of its ill-health consequences. The overall positive attitude score in this study was estimated to be 216 (63.5%).
Practice of health care providers on adult vitamin D deficiency
Only 46(11.4%) of health care workers reported that they have diagnosed adult patients for vitamin D deficiency in their professional career, of those 26(56.5%) of them diagnosed 1–3 patients of any age on an average working month (see Table 4). When asked on mechanisms of diagnosis 41(89.1%), did it by making clinical examination, 26(56.5%) measured serum vitamin D and 21(45.7%) used a combination of them. Moreover, 26(56.5%) revealed that they measured a concentration of 25 OH to assess vitamin D status.
Besides, only 50(12.4%) of study HCWs prescribed vitamin D supplementation for adults recently. Vitamin D supplementation for pregnant women was prescribed by only 3(0.3%) of the health care workers. Also, 13(3.2%) of health care workers used guidelines to recommend vitamin D supplementation. This study also revealed that 77(19.0%) of health care workers have given calcium supplement for adults to prevent the ill consequences of vitamin D deficiency in their full-service years. In addition to this, 64(15.8%) of health care providers usually counseled their adult patients about the importance of vitamin D deficiency. Meanwhile, 89(22.0%) of health care workers have advised adult patients about the source of vitamin D and 53(13.1%) of them asked their patients about the adequacy of sunlight exposure for vitamin D. Moreover, 86(21.2%) of health care workers counseled their adult patients on the need for sunlight exposure to get vitamin D. However, only 26 (6.4%) of health care providers received an on-job training or workshop on diagnosis of deficiency and treatment of vitamin D.
Factors associated with the practice in measuring vitamin D status, diagnosis of deficiency, and management and treatment of its ill health consequences:
The practice in measuring vitamin D status, diagnosis of deficiency, and management and treatment of ill-health conditions is significantly different among providers deployed in the three ecologies, which is higher among health workers working in Addis Ababa followed by those working in the rural highland district (Table 5). Male providers had a significantly better practice compared with females and as the age of the provider increases the practice level is improving. Obviously, clinicians have a better practice compared with those assigned in leadership and health promotion positions though the difference is not statistically significant. The practice level was significantly better among physicians and health officers, whose trainings have more emphasis on clinical orientation. Moreover, those workers who worked for several years had a significantly better practice level compared with the junior ones. In addition to this, health workers who have good knowledge and attitude had better practice in measuring vitamin D level, diagnosis of deficiency, and management of ill-health consequences.
Table 6 showed the binary logistic analysis to identify health care workers’ characteristics associated with their practice in measuring vitamin D level, diagnosing deficiency, and management and treatment of ill-health consequences. The odds of vitamin D service provision practice was AOR = 6.87: 95% CI (3.57, 13.21) times statistically significantly higher among health care workers deployed in Addis Ababa and AOR = 2.20: 95% CI (1.23, 3.92) times statistically significantly higher in the rural highland compared with those health care workers deployed in the rural lowland area. The likelihood of male health care workers’ practice in the provision of vitamin D related service was AOR = 1.26: 95% CI (0.71, 2.22) times statistically significantly higher compared with females. However, the difference in the odds of practice in vitamin D service provision vanished when it is adjusted for other socio-demographic factors.
Besides, the likelihood of clinicians’ practice in the provision of vitamin D service was AOR = 4.26: 95% CI (1.48, 12.25) times statistically significantly higher compared with those working in leadership and health program positions. The difference in the odds of competency in vitamin D service provision among different professional groups vanished when it is controlled for other socio-demographic factors. The same is true for the service year of health care workers.
On the other hand, the adjusted odds of practice in vitamin D service provision was AOR = 1.96: 95% CI (1.19, 3.23) times statistically significantly higher among those health care workers who have a good knowledge on vitamin D related service compared with those with poor knowledge. Besides, the likelihood of better practice in vitamin D service provision was AOR = 2.30: 95% CI (1.40, 3.78) times statistically significantly higher among those health care workers with a positive attitude in vitamin D service provision compared with those who did have a negative attitude.