Design

We conducted focus groups to explore all the relevant perceived determinants of intention to accept pertussis vaccination. A focus group encourages interaction between the participants, which facilitates a rich discussion[42]. If no focus group was possible due to organisational constraints, individual interviews were carried out.

Study participants

We selected parents of newborn babies and three different subgroups of healthcare workers: maternity assistants, midwives, and paediatric nurses, as they reflect groups, which are in close and prolonged contact with newborns. The study was performed in the Netherlands, a country where both maternal pertussis vaccination as well as pertussis cocooning were not implemented during the study period. In the Netherlands governmentally advised vaccination programmes are normally paid for by the government, which was the assumption of the interviewees during the interviews.We organised homogeneous focus groups between May 2011 and June 2012.

Data collection

The focus groups and interviews lasted around 1.5 hours, and a trained moderator (OV) and a research assistant (JW or LK) conducted them. We used a semi-structured interview guide, which was based on themes derived from the available literature and a barrier framework[18,24–26,43–46]. The same interview guide was used both for the focus groups as well as the interviews.

The interview topics included personal, external (social and societal), and organisational factors[18] We revised the interview guide after a pre-test. New themes that emerged during the focus groups and interviews were intuitively added to the interview guide by the researcher, to be verified in the next focus groups and interviews. New focus groups and interviews were planned for each group until no new concepts or themes emerged and theoretical saturation occurred.

Before enrolment, all participants had received a leaflet with information regarding the purpose of the focus group or interview, the voluntariness of participation, and a short introduction to the pertussis cocooning strategy. The focus groups and interviews started with an introduction to the study objectives and the role of the participants during the focus group, where the interactive character of the meeting was emphasised. The participants were assured that everything they said would be anonymous and confidential, and we asked their consent to record the focus group. Then, we introduced the key question for the focus group: ‘Why would you accept or refuse pertussis vaccination if it were offered to you in the context of a cocooning programme?’ We assured the participants that we were interested in arguments both for and against acceptance, and we asked them to write down these reasons for themselves first. An open group discussion followed, and the moderator asked more in-depth questions. The assistant checked whether all the topics taken from the interview guide had been covered and introduced a theme where relevant. In order to ascertain whether new arguments would arise for respondents, in case they would have access to more detailed information on pertussis and vaccination, we then handed out a sheet with factual information about pertussis and the proposed vaccination (comparable to information routinely provided in public health leaflets) to the participants. Then the group discussed this information.

Analysis

The focus groups and interviews were recorded with a digital voice recorder and transcribed verbatim by an independent transcriber (RW). The moderator and a research assistant independently coded all the focus groups and interviews. They used the qualitative software programme Atlas.ti for this purpose. We performed a thematic content analysis after completion of all focus groups and interviews and extracted main themes by means of both an inductive approach and a deductive approach. The moderator and research assistant discussed the codes and themes. They discussed any disagreements further until they achieved consensus. This study adheres to the Coreq guidelines for reporting qualitative studies[47].

Ethical review

The Medical Ethics Committee of the Arnhem—Nijmegen region assessed the study and concluded that it was exempt from their approval; reference number: 2010/475.

Risk perception

In deciding whether to accept pertussis vaccination, all groups evaluated their perception of three risks relative to the vaccination strategy: (1) the risk of pertussis disease for an infant, (2) the risk that they would transmit pertussis to an infant, and (3) their own risks due to vaccination. Within all participant groups, opinions differed on how to cope with risks, ranging from a risk-averse stance to the view that risks are an inevitable part of life.

Outcome expectations

The expectations participants had about the outcomes of the cocooning strategy were important in forming opinions. This was reflected in how they perceived the efficacy of the programme, as well as the expected benefits versus the expected costs.

General vaccination beliefs

The opinions of vaccination in general are reflected in the evaluation of pertussis vaccination in the context of cocooning. Some participants stated that vaccination in general is routine; for them, it is just the normal thing to do. They trusted the government or science to prescribe a vaccination only if it was unquestionably ‘a good idea’. Not all people for whom the National Immunisation Programme (NIP) was routine automatically thought pertussis cocooning was routine as well. Mainly parents expressed this view.

If people (i.e. government employees, OV) have come up with this solution, I guess it will be all right.

–Parent

Further, other participants had rather critical beliefs about vaccination in general. Their arguments belonged to three groups. First, they criticised the necessity of new vaccines. They asked themselves: ‘where will it all end?’ They wondered if cocooning just reflected a lobby of the pharmaceutical industry promoting the use of a new vaccine. Second, the participants were suspicious of vaccination in the sense that it was ‘not natural’. Some perceived a vaccination as ‘rubbish that is injected into your body’. Third, some participants claimed that naturally overcoming an infection would improve their health. Notably, most respondents with this critical mindset were professionals.

Isn't it supported by an enormous politically motivated group, or a pharmacological group that has earned lots of money with it?

–Neonatal care nurse

Moral norm

While evaluating their intention to accept pertussis vaccination for cocooning if it were offered to them, the participants’ moral norms seemed to influence them. They gave arguments about their feelings of responsibility and the justification of the programme.

Opinions of others

While some participants said they would decide about vaccination by themselves, others clearly stated that they would value discussion with like-minded people before deciding. Yet all the participants were conscious of other people’s opinions of vaccination. Professionals and parents alike tended to value the opinions of people with the relevant medical expertise. The opinions of family and friends were also important to parents. The professionals also said their colleagues influenced their opinions. However, maternity assistants were an exception: they said their profession was so solitary that they hardly had a chance to discuss such topics with their colleagues.

Among colleagues we sometimes talk about things during a break. One knows more about this and another about that, so eventually your decisions are better reasoned. At least you know for a fact that you have really given it some thought.

–Neonatal care nurse

Perceived autonomy

In the interviews, all the participants discussed the need to critically appraise their opinions of pertussis vaccination themselves. Some stated that the right to choose freely should not always prevail because the negative consequences of some choices could harm others. Nonetheless, such a restriction on their own choices led most participants to reject the offer of vaccination. This was most explicit among the maternity assistants when they recounted their experience with the Pandemic 2009H1N1 influenza. The pressure from their employers to accept vaccination negatively influenced their decision then and would do so again in the future.

Yes, mainly because it is very important to decide about your own body… after all, despite the best intentions, if people cannot choose for themselves, they'll object by saying: “Hey it is my body you are injecting.

–Neonatal care nurse

Anticipated regret

Another influential factor in considering pertussis vaccination is the possibility of a future consequence of their decision that the participants would regret. They mainly referred to the possible consequences of not being vaccinated. If a child in their environment then contracted pertussis, they would seriously regret it and feel guilty about not accepting pertussis vaccination. This argument emerged in all the groups. The midwives added an extra dimension to this argument: they would also regret losing income from their private practices if they became ill themselves. Some participants would also regret accepting the vaccination if they suffered physical problems at some point in the future that they thought the vaccination caused.

Of course it’s terrible when a child falls ill, especially a very small child, but if you knew you could have prevented it, you'd never forgive yourself.

–Parent

Decisional uncertainty

The amount of doubt participants showed in their deliberation about accepting the vaccination seemed to influence the decision. Some participants had confidence in their own opinion because of their education or their trust in the governmental organisations that provided the guidelines. Others believed they should be able to make an educated decision, but felt inadequately equipped to do so. When the participants tried to explain their uncertainty, they said it seemed to have become more difficult to handle the information for their decision because more and more information—often with contradictory messages—had become available. They then tried to verify the information and take into account the objectivity and reliability of the source and the evidence base, as well as the consistency of the message coming from different sources. Referring to the Pandemic 2009H1N1 influenzain 2009, the participants said that the more unrest they perceived in society and the more often messages appeared in the media, the less trust they had and the more difficult their decision would be. Both parents and healthcare workers recognised their decisional uncertainty.

What bothers me most was that both websites boast scientific underpinning. What I would like is one objective website because now one of them is for and the other is against, and how are you supposed to compare the two? Flip a coin?

–Parent

Perceived organisational barriers

Although the location, time, and vaccine provider of the future pertussis vaccination programme seemed to influence all the groups, they thought other issues were the most important ones.

Some parents believed it would be best if mothers were re-vaccinated before pregnancy, but at the same time they questioned the practical implications of this advice. The concept of vaccinating the mother right after birth caused some specific concerns about the vaccination location. They said that having to go to a specific health clinic for vaccination would reduce their willingness to accept. For them, the vaccine provider was a lesser issue; combining the vaccination with an already standard appointment seemed more important.

For neonatal care nurses and maternity assistants, the vaccine would be most logically provided via the occupational health service. However, community midwives who work in their own private practices with busy shift schedules often have no arrangements with an occupational health service. If the organisation around administering a vaccination were their own responsibility, that would hinder acceptance. All the professionals stated that an easily accessible location for vaccination with flexible timing options would facilitate their acceptance.

Logistically, things have not been arranged, things like where to get it since we're not a group. In an institution or an organisation you can apply to your manager or your work regulations. But we are self-employed, so where do we go? We can go see our general practitioner and pay.

–Midwife

Determinants of pertussis cocooning acceptance

In this study, we have identified nine perceived determinants of intention to accept pertussis cocooning among different target groups in the Netherlands. Five of these determinants (i.e. risk perception, general vaccination beliefs, the opinions of others, perceived autonomy and organisational issues) have been previously identified in studies of pertussis cocooning acceptance [20–41], albeit in a slightly different form. We have added perceived cost-effectiveness (as a concept of outcome expectations), justice (as a concept of moral norms), anticipated regret, and decisional uncertainty as perceived determinants of the intention to accept pertussis cocooning.

Experience, information, and trust

In reflecting on our data, we noticed three predominant themes rooted in the different determinants of intention to accept pertussis vaccination: experience, information, and trust. These themes might be important in understanding the decision-making for pertussis cocooning vaccination, and they might provide entry points for the design of an effective vaccination programme.

Participants’ experiences are important in their assessment of the various risks for their decision–making, and these experiences are also important in formulating the roles of autonomy and decisional uncertainty. In previous studies associations have been described between earlier vaccine acceptance (for instance for influenza) and present acceptance of a pertussis cocooning vaccination [23,27,28,32]. Although a person’s experiences are, of course, inalterable, their importance in decision-making might justify further study of how experience can help in interventions for encouraging acceptance of vaccination.

Studies for improving the acceptance of vaccination often recommend attuning information to the needs of target groups[43,45,65]. In line with these findings, most study participants indeed needed information; they asked many questions before they formed an opinion about vaccination for pertussis cocooning. In search for answers, they reported to value information based on the source, volume, consistency and scientific base. Knowing what information to trust seemed to be a difficult task, as some participants stated that their search for answers resulted in decisional uncertainty. Notably, part of our participants also stated they perceived public health information biased in favour of vaccination promotion, which added to their uncertainty. This could be understood to be a result of their awareness of the double role a government has in voluntary vaccination programs: to stimulate vaccination acceptance, while respecting and fostering the public’s autonomous choice on vaccination [66]. It also fits with the societal change in trust described in the next paragraph. Moreover, it suggests that the power of public health authorities to improve vaccination acceptance through information provision might be restricted.

Other studies in which uncertainty appeared report that providing extra, attuned information had limited effects on vaccination acceptance[67,68]. Some authors have even questioned whether information that provides arguments for choosing leads to a decision at all[69]. Thus, the role of information in decision-making in vaccination acceptance is controversial. Therefore, attention should be given to alternatives for information provision in vaccination programmes aimed at optimising acceptance.

Trust is currently a more often debated issue in the literature about vaccination acceptance[49,70,71]. In our findings, the importance of trust is reflected in its influence on the acceptance of pertussis vaccination via the general vaccination beliefs, perceived efficacy, and decisional uncertainty. Trust in government, science, and industry positively influenced acceptance because some participants believed that a vaccination would only be advised if positive outcomes were expected. In contrast, some participants formulated what we called ‘critical vaccination beliefs’ in which distrust was very important. This corresponds with the changes in society toward a risk culture in which manufactured risks seem exceedingly important and lead to the distrust of government, industry, and science[72,73] Such a culture has been described in the sociological literature[49,74–76]. An answer to this trend is not easily found, but we need to give it specific attention in future research about vaccination acceptance.

Differences between target groups

Notably, most determinants were brought forward by parents as well as professionals and were generally comparable in the different groups. Nonetheless, specific groups emphasised certain determinants.

The most remarkable differences were noted between the parents and the healthcare professionals, especially for moral norms, both responsibility and justiceMost parents said they could see vaccination as a part of their responsibility for their child’s health. Professionals, however, saw vaccination having an impact on their personal lives; therefore, they refused to regard it as part of their professional responsibility. This is compatible with Baron-Epel’s qualitative study of pertussis cocooning vaccination[21]

Furthermore, the healthcare professionals most clearly expressed critical vaccination beliefs, doubts about the risks for the vulnerable infants for whom the programme is designed, and doubts about the expected efficacy of the programme. It is remarkable that the healthcare professionals, who have more knowledge about medicine and science, held more beliefs that seemed to contrast with this background. However, this is in line with studies that identify higher educated parents and healthcare professionals as risk groups for vaccine refusal[77–79] Pereti-Watel[74] offers an explanation for this phenomenon: the educated middle class is more hesitant about accepting vaccination on the basis of distrust. They seem to know enough to recognise ‘manufactured risks’, but too little to discard them as illegitimate science.

Strengths and limitations

This study has some strengths and limitations that should be mentioned. First, it provides insight into a broad range of influencing factors that affect the intention to accept vaccination for pertussis cocooning in the Netherlands. We interviewed parents and healthcare professionals in four differing but relevant target groups, who have close and prolonged contact with newborns. Therefore, our data reflect a comprehensive range of determinants. This is one of the few studies to report a perspective of healthcare professionals as recipients of pertussis cocooning vaccination (rather than providers) Regrettably, we were able to conduct only individual interviews with the neonatal care nurses. However, the influence this had on the results appears limited, since no new themes emerged in these interviews. There could have been some selection bias: people with strong opinions about the subject might have been more inclined to enter the study. However, we met both advocates and opponents of vaccination in the focus groups and interviews. As we sampled parents from different socio-economic settings, we trust that most opinions possibly related to socio-economic background were covered. For this reason, we are confident that we have covered the broad array of the target groups’ arguments, both for and against vaccination. As organisation of health care varies between countries, our findings on organisational barriers may be not generalizable for other countries.

Second, the qualitative research method has the advantage of obtaining in-depth understanding of the factors in question. The inclusion of new participants until data saturation was achieved and the number of individual interviews and focus groups ensures good validity of the data.