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ORIGINAL ARTICLE
Year : 2018  |  Volume : 21  |  Issue : 2  |  Page : 75-82

Cold chain management: An assessment of knowledge and attitude of health workers in primary health-care facilities in Edo State Nigeria


Department of Community Health, College of Medical Sciences, University of Benin, Benin City, Nigeria

Date of Web Publication6-Jul-2018

Correspondence Address:
Dr. Esohe Olivia Ogboghodo
Department Of Community Health, College of Medical Sciences, University of Benin, PMB 1154, Benin City
Nigeria
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/smj.smj_45_17

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  Abstract 


Background: The use of vaccination to prevent diseases is the greatest public health success of the last century. Due to the sensitive and labile nature of vaccines, appropriate measures need to be put in place to ensure that vaccines remain potent from point of manufacture to administration. Adequate knowledge of cold chain management by health workers is necessary to manage vaccines appropriately and efficiently to ensure the vaccines remain potent. Objective: The objective of this study is to assess the knowledge and attitude toward cold chain management among health workers in primary health-care (PHC) facilities in Benin City, Edo State. Materials and Methods: This was a descriptive, cross-sectional study among health workers working in PHC facilities offering immunization services in Benin City. The participants were selected using multistage sampling technique. Data were collected using pretested structured self-administered questionnaires and data analysis was by IBM SPSS (IBM Corp, Armonk, New York, United States) version 21.0. The level of significance was set at P < 0.05. Results: Of the 425 respondents who participated in the study, 272 (64.0%) had poor knowledge while 396 (93.2%) had positive attitude toward cold chain management. Determinants of knowledge were cold chain management training (P = 0.018), presence of functional refrigerators (P = 0.011), and National Programme on Immunization supervision (P < 0.001). Determinants of attitude were level of education (P = 0.005) and knowledge of cold chain management (P < 0.001). Conclusion: The study showed a gap in knowledge and good attitude toward cold chain management among the respondents. All stakeholders should ensure collective effort in improving the knowledge and attitude of health workers toward cold chain management.

Keywords: Cold chain management, Edo State, health-care workers, knowledge and attitude, Nigeria


How to cite this article:
Ogboghodo EO, Omuemu VO, Odijie O, Odaman OJ. Cold chain management: An assessment of knowledge and attitude of health workers in primary health-care facilities in Edo State Nigeria. Sahel Med J 2018;21:75-82

How to cite this URL:
Ogboghodo EO, Omuemu VO, Odijie O, Odaman OJ. Cold chain management: An assessment of knowledge and attitude of health workers in primary health-care facilities in Edo State Nigeria. Sahel Med J [serial online] 2018 [cited 2024 Mar 28];21:75-82. Available from: https://www.smjonline.org/text.asp?2018/21/2/75/236065




  Introduction Top


The use of vaccination to prevent diseases is one of the greatest public health success of the last century.[1] Vaccination has greatly decreased the burden of infectious diseases globally and has dramatically decreased the threat of diseases that were once widespread and often times fatal.[2] In the US, the Center for Disease Control and Prevention estimates that vaccinations have prevented >21 million hospitalizations and 732,000 deaths among children born in the last 30 years.[2] Vaccine-preventable diseases (VPDs) are responsible for nearly 20% of the 8.8 million deaths/year among children under-5 years.[3] VPDs such as pneumonia, diarrhea, and measles account for about 40% of all deaths among under-five children in Nigeria.[4] This has been attributed to poor routine immunization performance, caused by logistics and supply chain infrastructure issues, failure of the cold chain and inadequate knowledge among health workers regarding cold chain management.[4]

For vaccine delivery system to be successful, essential vaccine needs to be available and of good quality because it is only when potent and efficacious vaccines are administered that successful immunization can be actualized. Hence, the quality of immunization delivered, can only be ensured by a functional cold chain system. Nigeria failed in achieving Millennium Development Goal 4, to reduce mortality among children under the age of 5 by two-thirds from 1990 to 2015.[4] This is in spite of several efforts by the government through the National Primary Health Care Development Agency (NPHCDA) to ensure vaccine availability and coverage through routine vaccine supply and supportive supervision of health workers involved in immunization services.[4] In some settings in Nigeria, many health facilities offer immunization without adequate knowledge of vaccine administration and management. This may cause possible administration of nonpotent vaccines to the populace.[1] Reports from developing countries indicate that health workers seem to be overwhelmingly concerned with only raising vaccination coverage oftentimes to the detriment of vaccine potency.[5] Suboptimal seroconversion rates and outbreaks of VPDs elsewhere were attributed to loss of vaccine potency either during transportation or storage. Reports have shown that while vaccination coverage seems to be on the increase, the prevalence of VPDs has not reduced.[5],[6] The quality of vaccination services which is important for achievement of disease reduction is being neglected due to poor knowledge and attitude, as health workers seem to focus less on maintaining vaccines in the cold chain and more on ensuring coverage.[5]

Inadequate knowledge of cold chain management could lead to improper handling of vaccines by health workers which would result in altered potency of vaccines. Poor knowledge of cold chain management could also result in a failure of the health worker to recognize that the potency of vaccine has been compromised. This may lead to inadvertent administration of subpotent vaccines, which increases the risk that beneficiaries are not fully protected from disease.[7] In addition to knowledge, the attitude of health workers toward cold chain management is a pointer to how committed they are in ensuring knowledge acquired is translated into effective practice. Hence, this study was conducted to assess the knowledge and attitude of health workers in primary health care (PHC) facilities in Benin-City, Edo State, toward cold chain management.


  Materials and Methods Top


The study utilized a descriptive, cross-sectional study design. The study population comprised health-care workers involved in immunization services in selected public and private health facilities in Benin City, Edo State. A minimum sample size of 422 using the formula for single proportion [8] was used. This was calculated considering a standard normal deviate of 1.96 at a significance level of 5%, degree of precision of 5%, 51.4% level of correct knowledge of vaccine vial monitor in private health facilities in Lagos,[1] and a 10% attrition rate (nonresponse). A multistaged sampling technique comprising 3 stages was used to select respondents. A list of all the three LGAs in Benin City was obtained and Egor and Oredo LGAs were selected using simple random sampling technique by balloting. Six wards were selected from each LGA by balloting having obtained a sampling frame of all the wards in each selected LGA. There are a total of 104 health facilities in Egor LGA and 167 primary health facilities in Oredo LGA. All health facilities (both private and public primary health facilities) in the selected wards that offer immunization services (27 in Egor LGA and 26 in Oredo) were selected for this study. All health workers in selected health facilities who met the inclusion criteria were recruited for the study.

Data were collected using a pretested structured self-administered questionnaire comprising both open- and closed-ended questions and consisting of 3 sections. Section A sought information on the sociodemographic characteristics of the respondents, Section B sought information on respondents' knowledge of cold chain management, and Section C consisted of questions that assessed respondents' attitude toward cold chain management. A pretest of the study tool was conducted in PHC facilities in Ovia North-East LGA, Benin City. Pretesting was done to enhance clarity, comprehensibility, validity, and reliability of data tools, and corrections were effected before commencement of the study. Ethical approval to conduct this research was sought and obtained on 21st June 2016 from the Research Ethics Committee, College of Medical Sciences, University of Benin, Benin City. The study was described to the health workers and written informed consent was obtained from respondents. Respondents were informed that they had the right to decline participation or to withdraw from the study at any time they wished.

The questionnaires were screened for completeness by the researcher after which they were coded, entered into the IBM SPSS version 21.0 software and analyzed. According to the NPHCDA; National Routine Immunization Strategic Plan, National Programme on Immunization supervision was grouped into ≥ thrice a month and less than thrice a month.[9] Knowledge was assessed using a total of 29 questions under 5 domains. For each question, a score of 1 was awarded for a correct answer and 0 for a wrong answer. The total knowledge score for each respondent was converted to percentages. Scores below 50.0% were categorized as poor knowledge and scores that were 50.0% and above were categorized as good knowledge. A value of 0.815 was obtained after assessing the questions used in scoring knowledge using the Cronbach's alpha test. Attitude toward cold chain management was assessed using a total of 7 questions on a 3-point Likert scale. The most positive response to a question was given a score of 2 while the most negative response to a question a score of 0. The total attitude score for each respondent was converted to percentages. Scores below 50.0% were categorized as negative attitude and scores that were 50.0% and above were categorized as positive attitude. The questions used in scoring attitude were assessed for internal consistency and reliability using the Cronbach's alpha test, and a value of 0.787 was obtained.

Test of associations were carried out using Chi-squared tests or the Fishers' Exact test where appropriate. Multivariate analysis using binary logistic regression was carried out using the 'enter approach' to further determine the significant predictors of the knowledge and attitude towards cold chain management and control for confounders. The statistical measure for the analysis was the adjusted odds ratio (OR) and 95% confidence interval (CI). The level of significance was set at P < 0.05 for all statistical associations. Frequency tables were used to present the results.


  Results Top


A total of 425 respondents participated in the study. The mean age was 37.5 ± 8.7 years with a proportion of 153 (36.0%) seen in the 25–34 year age group. Three hundred and seventy-one respondents (87.3%) were females, and 420 (98.8%) practiced Christianity [Table 1]. A higher proportion of respondents 291 (68.5%) had tertiary level of education, and 169 (39.8%) of the respondents were Community Health Extension Workers (CHEWs). A higher proportion of respondents 267 (62.8%) had been administering vaccines for >5 years [Table 1].
Table 1: Sociodemographic characteristics and cold chain management training and supervision status of respondents (n=425)

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Three hundred and one (70.8%) of the respondents had received training in cold chain management and of these 189 (62.8%) had their last training more than a year before the study. A greater proportion of respondents 348 (81.9%) worked in health facilities that had NPI supervision. Of these, 64 (18.4%) received NPI supervisory visits thrice a month and above [Table 1]. A higher proportion of auxiliary nurses 85 (81.0%) had received training in cold chain management compared to registered nurses 94 (62.3%) and CHEWs 122 (72.2%), and this was statistically significant (P = 0.005).

All respondents 425 (100.0%) had heard of cold chain with the majority 388 (91.3%) indicating the workplace as their source of information. A majority 351 (82.6%) knew the correct definition for cold chain while 292 (68.7%) had a good knowledge of cold chain equipment. The knowledge of cold chain monitoring and freeze sensitive vaccines was poor among a higher proportion of respondents, 265 (62.4%) and 329 (77.9%), respectively. Just over half of the respondents 216 (50.8%) had poor knowledge of heat sensitive vaccines, and 407 (95.8%) had good knowledge of benefits of cold chain management. A higher proportion of respondents 272 (64.0%) had an overall poor knowledge of cold chain management [Table 2].
Table 2: Knowledge of cold chain management of respondents

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Respondents with a tertiary level of education had better knowledge of cold chain management 121 (41.6%) than those with secondary level of education 32 (23.9%). This difference in knowledge of cold chain management observed with increasing level of education was statistically significant (P < 0.001) [Table 3]. With increasing level of education, respondents were 11.597 times more likely to have good knowledge (P < 0.001, CI = 5.297–25.387) [Table 4]. Ironically, a higher proportion of auxiliary nurses had good knowledge of cold chain management 46 (43.8%) as compared with registered nurses and CHEWs, 52 (34.4%) and 55 (32.5%), respectively. However, the association between knowledge and cadre of health-care worker was not statistically significant (P = 0.148) [Table 3]. Auxiliary nurses were more likely by an OR of 6.833 to have good knowledge of cold chain management, and this was statistically significant (P < 0.001, CI = 3.308–14.112) [Table 4].
Table 3: Sociodemographic variables and knowledge of cold chain management

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Table 4: Logistic regression model for determinants of knowledge of cold chain management

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Good knowledge of cold chain management was higher 18 (51.4%) among respondents that had been administering vaccine for less than a year. However, from then onward, knowledge was found to be better with increasing number of years of vaccine administration. The association between duration of vaccine administration and knowledge of cold chain management was statistically significant (P < 0.001) [Table 3]. With increasing number of years of vaccine administration, respondents were less likely by an OR of 0.951 to have good knowledge, and this was not statistically significant (P = 0.737, CI = 0.711–1.273) [Table 4]. A higher proportion of respondents who had received training on cold chain management 119 (39.5%) had good knowledge of cold chain management compared to those who had not had any training 34 (27.4%). The association between training in cold chain management and knowledge of cold chain was statistically significant (P = 0.018). Good knowledge of cold chain management was higher among respondents who had had their training less than a year 55 (49.1%) compared to those who had their training more than a year before the study 64 (33.9%). This difference in knowledge observed with time of last training was statistically significant (P = 0.010).

Good knowledge of cold chain management was higher among respondents whose health facility (HF) received NPI supervisors 145 (41.7%). The association between NPI supervision at HF worked in and knowledge of cold chain management was statistically significant (P < 0.001) [Table 3]. Having NPI supervision at HF increased the likelihood of having good knowledge of cold chain management by an OR of 7.960, and this was statistically significant (P < 0.001, CI = 3.733–16.972) [Table 4]. A majority 419 (98.6%) of respondents agreed that cold chain is crucial for maintaining vaccine potency. Three hundred and seventy-eight (88.9%) of the respondents had the perception that food and drinks should not be placed together with vaccines in refrigerator. A higher proportion of respondents 287 (67.5%) disagreed that refrigerators should be opened more than 3 times a day and almost all respondents 423 (99.5%) disagreed that vaccines should be used after expiration. Three hundred and ninety-six (93.2%) of respondents had an overall positive attitude toward cold chain management [Table 5].
Table 5: Attitude toward cold chain management of respondents

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A greater proportion of respondents with tertiary level of education 275 (94.5%) had positive attitude toward cold chain management as compared with respondents with secondary level of education, 121 (90.3%). However, this difference in attitude observed with increasing education was not statistically significant (P = 0.110) [Table 4]. After adjusting for covariates, the chances of respondents having an overall positive attitude increased by an OR of 4.189 with increasing level of education, and this was statistically significant (P = 0.005, CI = 1.526–11.497) [Table 6]. Similar proportion of registered nurses and CHEWs were found to have a positive attitude toward cold chain management, 141 (93.4%) and 158 (93.5%), respectively, with a slightly lesser proportion observed among auxiliary nurses, 97 (92.4%). The association between occupation of respondents and attitude toward cold chain management was not statistically significant (P = 0.932). Auxiliary nurses were more likely by 1.709 to have an overall positive attitude toward cold chain management compared to registered nurses and CHEWs; however, this was not statistically significant (P = 0.294, CI = 0.628–4.650) [Table 6].
Table 6: Logistic regression model for determinants of attitude towards cold chain management

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Positive attitude toward cold chain management was higher among respondents who had had training in cold chain management 282 (93.7%). The association between training in cold chain management and attitude toward cold chain management was statistically significant (P = 0.003). Attitude toward cold chain management was better among respondents who had their last training in cold chain management less than a year before the study 111 (99.1%). The association between time of last cold chain management training and attitude toward cold chain management was statistically significant (P = 0.003). Respondents who received NPI supervisors at their HFs had a higher proportion of those who had a positive attitude 325 (94.5%) compared to those who did not receive NPI supervisors at their HFs 81 (87.0%). The association between NPI supervision at HF and attitude was however not statistically significant (P = 0.075) [Table 7]. This observation was maintained after adjusting for covariates, health workers who received NPI supervision at their health facilities were more likely by an OR of 2.047 to have positive attitude toward cold chain management, this was, however, not statistically significant (P = 0.081, CI = 0.916–4.572) [Table 6]. A higher proportion of respondents who received NPI supervision thrice a month and above 63 (98.4%) had a positive attitude toward cold chain management compared to those who received NPI supervision less than thrice a month 266 (93.7%). The association between frequency of NPI supervisor visits and attitude toward cold chain management was statistically significant (P < 0.001).
Table 7: Sociodemographic variables of respondents and attitude toward cold chain management

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  Discussion Top


As expected, all respondents that participated in this study were aware of cold chain management with majority indicating the workplace as their source of information. This is due to the fact that this study was carried out among only health workers that administer vaccines. Although awareness was high, over two-thirds of respondents had an overall poor knowledge of cold chain management. This is in contrast with results of a study done in Coastal South India in 2012 where the majority of respondents had an overall good knowledge of cold chain management.[5] It is noteworthy that a high proportion of those who had received training did so >1 year before the study. This may account for this finding of poor knowledge in our study. This finding is further supported by the fact that respondents who had been administering vaccines for less than a year were found to have a better knowledge than other respondents. Poor knowledge of cold chain management may lead to the poor practice of vaccine storage and cold chain monitoring as respondents may not be able to recognize if the cold chain is defective at any point and this may lead to damage of vaccines hence, culminating in wastage of vaccines which have been stated to be expensive.[10],[11]

Greater than nine-tenths of respondents had good knowledge of the benefits of cold chain management. This could positively influence the respondents' attitude toward cold chain management and strengthen their resolve to do the best they can with regard to preserving vaccine potency. A higher proportion of auxiliary nurses had good knowledge of cold chain management as compared with registered nurses and CHEWs. This may be because auxiliary nurses were shown in this study to have received more training in cold chain management compared to registered nurses and CHEWs. Knowledge of cold chain management was found to be better among respondents who had had some training in cold chain management. Furthermore, those who had their training less than a year before the study were also found to have better knowledge. Training in cold chain management serves to remind the respondents of what they had learnt previously, impact new knowledge and teach them how best to apply the knowledge they have gained to yield effective results. In addition, regular training is very important as this affords them an opportunity to obtain up-to-date information on cold chain management in line with the world's best practices at that time. The fact that a majority of respondents who had had their training in cold chain management had the last training greater than a year ago is a pointer to how laid back these respondents may be and this could be due to poor understanding of the importance of training, as well as poor enforcement by supervisory bodies. This is dangerous as it exposes the cold chain to possible mishandling by respondents with poor knowledge and this could ultimately lead to dire consequences in the long run.

NPI supervision was also found to be another strong determinant of knowledge of cold chain management among respondents as a greater proportion of respondents who received NPI supervisors at their HFs had good knowledge of cold chain management compared to those who had no supervision. This is in tandem with findings from a study conducted in Lagos Nigeria in 2010.[1] This could be attributed to the fact that supervisors in the course of carrying out their jobs are better able to identify areas where the workers are deficient in knowledge of cold chain management and as a result fill in the missing gaps ultimately resulting in providing a boost to what they previously knew and hence, better knowledge.

Majority of the respondents had a positive attitude toward cold chain management. This is in contrast to findings from a study carried out in Kelantan, Malaysia, in 2013 where over three-quarters of respondents had a negative attitude toward cold chain.[12] This finding in our study could be due to the fact that respondents demonstrated an exceptionally good knowledge of the benefits of cold chain management. People's attitude in their workplace has been found to directly affect their job performance, decisions and turn-over.[13] More specifically, the success of cold chain management has been stated to depend mainly on the attitude of the cold chain handlers. Positive attitude toward cold chain management would enable the respondents to process the knowledge and information they have on cold chain management with greater awareness, efficiency, and more appropriately translate into better practice.


  Conclusion Top


A higher proportion of respondents had poor knowledge of cold chain management. A majority had a positive attitude toward cold chain management. Stakeholders involved in ensuring the success of cold chain management should ensure that they play their parts individually and collectively so as to ensure that the dividends of an efficient cold chain are enjoyed by all and sundry.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
  References Top

1.
Bankole A, Kola-korolo O, Bankole M, Iboma O, Adeluola A. The impact of health facility monitoring on cold chain management practices in Lagos, Nigeria. J Public Health Epidemiol; 2010;2:78.  Back to cited text no. 1
    
2.
Pfizer. The value of Vaccines in Disease Prevention. Pfizer: Value of Medicines; 2015. p. 1-3. Available from: http://www.pfizer.com/files/health/VOMPaper_Vaccines_R7.pdf. [Last accessed on 2016 Jul 12].  Back to cited text no. 2
    
3.
Praveen B. Cold Chain Qualification. Fierce Market Place Pharma Tech; 2015. Available from: http://www.stem-art.com/Library/Biobanking/Cold%20Chain%20Qualification%205%20Questions%20You%20Must%20Ask%20When%20Shipping%20Biologics.pdf. [Last accessed on 2016 Jul 21].  Back to cited text no. 3
    
4.
Federal Ministry of Health. National Primary Health Care Development Agency; National Routine Immunization Strategic Plan 2013-2015; Nigeria; 2013-2015. p. 13-27. Available from: http://www.nationalplanningcycles.org/. [Last accessed on 2016 Oct 07].  Back to cited text no. 4
    
5.
Rao S, Naftar S, Baliga S, Unnikrishnana B. Evaluation of awareness, practice and management of cold chain at the primary health centers in coastal South India. J Nepal Pediatr Soc 2012;32:19-21.  Back to cited text no. 5
    
6.
Arora V. Quality Assurance Plan for a Vaccine Preventable Diseases Surveillance Program. Texas Medical Center Dissertations (via ProQuest); 2009. AAI1462271. Available from: http://www.digitalcommons.library.tmc.edu/dissertations/AAI1462271. [Last accessed 2017 Apr 02].  Back to cited text no. 6
    
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Joao C, Gunnar B. Cold chain management: Knowledge and practices in primary health care facilities in Niassa Mozambique. Ethiop J Health Dev 2007;21:130-5.  Back to cited text no. 7
    
8.
Lalitha K, Anniappan A, Vderhobli N, Krishna S, Yathiraj S, Sreekantaiah P. Evaluation of cold chain practices in urban health centers of a Metro City in India. Natl J Community Med 2014;5:288-92.  Back to cited text no. 8
    
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Federal Ministry of Health. National Primary Health Care Development Agency; National Routine Immunization Strategic Plan 2013-2015; Nigeria: 2013-2015. p. 13-27.  Back to cited text no. 9
    
10.
Perry H, Zulliger R: How Effective Are Community Health Workers? An Overview of Current Evidence with Recommendations for Strengthening Community Health Worker Programs to Accelerate Progress in Achieving the Health-related Millennium Development Goals. Baltimore. John's Hopkins Bloomberg School of Public Health 2012;1-4.  Back to cited text no. 10
    
11.
Mangeni MN. Knowledge of Health Workers on Cold Chain and Logistics' Management for Expanded Program on Immunization in Busia and Namayingo Districts Eastern Uganda. 2013;1:8-10.  Back to cited text no. 11
    
12.
Azira B, Norhayati MN, Norwati D. Knowledge attitude and adherence to cold chain among general practitioners in Kelantan, Malaysia. Int J Collab Res Intern Med Public Health 2013;5:161-2.  Back to cited text no. 12
    
13.
Saari ML, Judge T. Employee attitudes and job satisfaction. Wiley Period 2004;43:395-407.  Back to cited text no. 13
    



 
 
    Tables

  [Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6], [Table 7]


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