Analysis of the impact of the level of knowledge on the decision to vaccinate

Introduction

Contagious diseases are still a significant issue in the modern medical – as well as social – world. One of the most effective methods of protection against contagious diseases is vaccination, as an active prophylaxis of infectious diseases. This method is thought to be the most efficacious and the cheapest measure to globally secure the health of the population. Thanks to obligatory preventive vaccinations the incidence and mortality rate of several infectious diseases, such as diphtheria, tetanus, and hepatitis type B [1], have been reduced.
In Poland vaccination is a common and mass procedure performed in accordance with the calendar/schedule of obligatory vaccinations. Vaccination may also be carried out in an individual manner considering recommended vaccinations. The realisation of prophylactic vaccinations in Poland has achieved a high level.
However, the parents’ shortage of knowledge regarding diseases whose incidence has been reduced due to vaccinations is worrying. There are faulty opinions, according to which vaccination is not necessary since the incidence of certain contagious diseases is very low. English research confirms this relation: there tend to be fewer mothers who think that such infectious diseases as poliomyelitis or pertussis (whooping cough) may bring about serious consequences should a child be affected [2].
There seem to be more and more anti vaccination groups, which, to promote their fallacious theories, use the lack of relevant knowledge among parents who know little about active immunisation, possible post vaccination complications, or the dangers stemming from a given disease [3–5].
Numerous studies show that a large number of parents do not have the necessary knowledge about the dangers resulting from infectious diseases, or about the preventive vaccinations to which their children are subjected according to the vaccinations schedule [1]. American researchers maintain that most persons think that disorders such as measles or pertussis will not occur since they are not occurring at present [2]. Erroneous conviction may cause a decrease of vaccination against these diseases, thus facilitating their new spread among the population. Also a lack of unbiased information about postvaccinal side effects delivered by medical personnel may generate among parents ideas of harmful effects caused by vaccinations, and thus enhance their fear of vaccination [6].
Therefore, proper education referring to prophylactic vaccinations is vital. The authority with which parents endow doctors should make a firm basis for re-shaping parental attitude toward vaccinations.

Aim of the research

The assessment of the impact of knowledge about vaccinations on the decision to perform obligatory and non-obligatory preventive vaccinations.

Material and methods

The study embraced 370 people (308 females and 62 males), students of Lublin colleges, as well as young parents living in Lublin Voivodeship. The test tool was an original questionnaire consisting of 20 closed questions. For the purpose of statistical analysis a descriptive statistical method was applied, using the c2 testand Cramer’s V correlation coefficient.
To assess the respondents’ knowledge, the respondents were asked about possible effects of vaccinations, the efficacy of vaccinations, and postvaccinal effects that might be dangerous to children. The respondents were also asked about illnesses that can be caused by vaccinations. Each tested individual could maximally score 30 points. Persons who scored 26–30 points were classified as persons well knowledgeable about prophylactic vaccinations. Persons who scored 21–25 points were classified as satisfactorily knowledgeable about vaccinations. Persons who scored less than 20 points were classified as deficiently knowledgeable about vaccinations.
The satisfactorily knowledgeable group was the largest (46%). Only 14% of the studied individuals were well knowledgeable about the subject. Almost 40% of the participants possessed little knowledge of vaccinations.

Results

A statistically significant relationship between the knowledge level and the studied subjects’ decision on future vaccination of their children according to schedule was observed. About 98% of the well knowledgeable persons declared they would have their children regularly vaccinated in accordance with the schedule. Persons who turned out to be moderately knowledgeable also declared they would have their children regularly vaccinated. Those whose knowledge of vaccinations was small did not care much about vaccination, and 49% of them stated that they would have their children vaccinated, although they did not think it would be of importance (Table I).
The respondents were also asked whether they would have their children vaccinated if the presently obligatory vaccinations were non-obligatory. Also in this case a statistically significant relationship (p < 0.001) between the knowledge level and willingness to have all vaccination done was observed. About 92% of highly knowledgeable persons were willing to have all the scheduled vaccinations administered to their children, even if they were non-obligatory. On the other hand, only approximately 28% of parents whose knowledge level was low wished to have all the recommended vaccinations administered. Most of these parents (63%) said they would not have their children vaccinated if the procedure were non-obligatory (Table II).
The participants of the study were also asked if they would undergo non-obligatory vaccinations recommended by physicians and pharmacists, e.g. vaccinations against influenza. In this case the level of knowledge was of significance too (p < 0.001). Persons characterised by high and medium level of knowledge on vaccinations more often declared regularity of non-obligatory vaccinations. As for the persons whose knowledge level was low, 62% of them would never be non-obligatorily vaccinated (Table III).
The influence of the economic factor on the decision to vaccinate was also taken into consideration. The respondents were asked if they would be non-obligatorily vaccinated, e.g. against influenza, if the procedure were free of charge (refunded). There was a statistical relationship (p < 0.001): persons of higher knowledge level declared they would regularly be vaccinated in such a case. The refund would not change the decision among persons whose level of knowledge was low; just 14% of them would be regularly non-obligatorily vaccinated. Individuals belonging to this group would employ non-obligatory vaccinations only in the case of direct danger of epidemic.

Discussion

A crucial factor that influences the decision on vaccination in the studied population is the knowledge of the subject. Persons not knowledgeable about vaccinations seldom decided to be vaccinated, e.g. against influenza. A similar relationship was observed by Dymek-Skoczyńska et al. in their studies, in which 29% of the subjects did not want to be inoculated with a vaccine against influenza because they had no knowledge of the effectiveness of vaccination [7].
A statistically significant relationship between the possessed knowledge on vaccination and the decision on vaccination in children was observed in the studied group. Knowledgeable parents more often declared readiness to have their children inoculated with obligatory and non-obligatory vaccines. A similar relationship was observed by Tarczoń et al. The studies showed that about 94% of parents who were aware of what diseases may be prevented by vaccination were in favour of obligatory and non-obligatory vaccinations of their children. Only 75% of the subjects without the knowledge of immunisation from a comparative group would support all prophylactic vaccinations [1].
There is justified concern that the low level of knowledge on vaccinations among parents may support the argumentation of anti-vaccination movements. The studies by Tarczoń et al. demonstrated that 40% of the subjects thought pertussis is a disease no longer in existence, and 15% of the subjects were also positive that measles does not occur in modern world [1]. Insufficient knowledge may result in the belief that vaccinations are not necessary, which in turn may lead to a decrease in vaccinations against these contagious diseases, and consequently a rise of their incidence in the future. It is also important that medical personnel propagate information about vaccinations and postvaccinal side effects, since a lack of such information may fossilise among parents false conceptions of undesired effects of vaccination, which in turn may enhance their fear of vaccination [8].
Physicians, an authority to most parents, and according to the studies by Mrożek-Budzyn et al., help to form parents’ opinions about vaccinations, and thus they should keep encouraging parents to have their children vaccinated [9–11].

Conclusions

The level of the knowledge influences the decision on vaccination. Knowledgeable persons more often have their children and themselves obligatorily and non-obligatorily vaccinated. Not knowledgeable persons are less interested in regularity of vaccinations in accordance with the schedule. Education conducted by qualified medical personnel plays an important role in propagating knowledge of preventive vaccinations.

Conflict of interest

The authors declare no conflict of interest.

References

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Address for correspondence:
Zofia Śliwińska
Wielospecjalistyczny Publiczny
Zespół Opieki Zdrowotnej w Zgorzelcu
ul. Lubańska 11, Zgorzelec, Poland
E-mail: zosia.sliwinska@interia.pl