|Year : 2022 | Volume
| Issue : 4 | Page : 296-302
Willingness to pay for a COVID-19 vaccine for oneself and one's child among individuals attending a tertiary care centre in West Bengal, India
Tanveer Rehman1, Ajay Mallick2, Farhad Ahamed3, Srikanta Kanungo1, Sanghamitra Pati1
1 Indian Council of Medical Research-Regional Medical Research Centre, Bhubaneswar, Odisha, India
2 Department of Otorhinolaryngology (ENT), All India Institute of Medical Sciences, Kalyani, West Bengal, India
3 Department of Community Medicine and Family Medicine, All India Institute of Medical Sciences, Kalyani, West Bengal, India
|Date of Submission||15-Jul-2022|
|Date of Decision||05-Sep-2022|
|Date of Acceptance||09-Sep-2022|
|Date of Web Publication||27-Oct-2022|
Department of Community Medicine and Family Medicine, All India Institute of Medical Sciences, Kalyani, West Bengal
Source of Support: None, Conflict of Interest: None
Background: The free-of-cost supply could not meet the demand for coronavirus disease-2019 (COVID-19) vaccines in India, so the government approved an injection option with a price. We aimed to determine how much money an individual would be willing to pay for a COVID-19 vaccine for themselves and their children and assess the factors determining it. Methods: We conducted a study among all adults visiting the outpatient department of a government tertiary care hospital in West Bengal, India, in August 2021. Trained nursing officers combined bidding game and open-ended question methods during personal interviews to estimate the willingness-to-pay (WTP) values. Results: The mean (standard deviation) age of 1565 participants was 40.8 (12.2) years with 46.5% (n = 727) males, 70.4% (n = 1102) parents, 50.0% (n = 783) educated upto class 12 and 30.9% (n = 483) belonging to upper-middle socio-economic scale (SES). The median (inter-quartile range [IQR]) WTP amount for the first dose and the subsequent/booster dose among the unvaccinated (50.2%, n = 785) and vaccinated (49.8%, n = 780) participants were ₹0 (0–100) and ₹0 (0–200), respectively. The median (IQR) WTP for inoculating children with any COVID-19 vaccine was ₹50 (0–300) in both groups. Significant differences were found in the WTP prices for adult vaccines in both groups concerning age category (P = 0.02), education (P < 0.01) and SES (P < 0.01). Conclusion: Although more than half of the respondents were unwilling to pay for themselves, WTP for COVID-19 vaccination was higher for their children. Policy-makers should consider income, education and age to cap the private sector vaccination price.
Keywords: Coronavirus disease-2019 vaccines, cross-sectional studies, health expenditures, India, parents, vaccination
|How to cite this article:|
Rehman T, Mallick A, Ahamed F, Kanungo S, Pati S. Willingness to pay for a COVID-19 vaccine for oneself and one's child among individuals attending a tertiary care centre in West Bengal, India. Niger Postgrad Med J 2022;29:296-302
|How to cite this URL:|
Rehman T, Mallick A, Ahamed F, Kanungo S, Pati S. Willingness to pay for a COVID-19 vaccine for oneself and one's child among individuals attending a tertiary care centre in West Bengal, India. Niger Postgrad Med J [serial online] 2022 [cited 2022 Nov 29];29:296-302. Available from: https://www.npmj.org/text.asp?2022/29/4/296/359762
| Introduction|| |
The global pandemic of coronavirus disease-2019 (COVID-19) has severely affected human lives. As of 19th May 2022, 520 million cases and six million deaths have been reported globally, whereas more than 43 million cases and 0.5 million deaths have been reported in India. The vaccination drive is an essential cost-effective public health intervention to mitigate the impact and spread of the deadly severe acute respiratory syndrome coronavirus-2 (SARS CoV-2). The consequences of missing doses could be devastating for individual families and the health-care system, as it would burden the already overcrowded health-care facilities. Vaccination programmes also provide a range of other benefits, such as disease control, prevention of drug resistance and overall economic and societal well-being, especially in low- and-middle-income countries (LMICs).
In India, most COVID-19 vaccines are being administered through the country's public health system, and its expenses, including the marketing strategies, are being borne by the Government of India (GoI). However, as the pandemic progressed, the demand for vaccines skyrocketed, but the supply often fell short of the requirement resulting in countless beneficiaries returning home without vaccination. Furthermore, crowds gathering in these vaccination centres jeopardise the measures of COVID-19-appropriate behaviours. Hence, GoI partnered with private hospitals to expand the vaccination drive. Recommendation for monetary valuation of a vaccine is a disputed subject − many factors such as the cost of the technology used and its storage and transportation influence the price capping. Since vaccination is a voluntary decision, increasing the cost may dampen the vaccination campaign. Accordingly, the willingness-to-pay (WTP) value will help policy-makers determine the affordable price for one dose of the COVID-19 vaccine for adults and children. In addition, WTP plays a crucial role in demand appraisal. The vaccination drive is presently targeted only towards the adult population, and the focus is gradually being shifted to vaccinating children between 2 and 18.
As discrete choice methods (DCMs) usually tend to be more exhausting and taxing for the participants, the contingent valuation method (CVM) is preferred to elicit WTP. CVM is a stated preference model that can measure the financial worth of consumers' place on specific aspects of health-care services that are not available to them (hypothetical).
WTP for a COVID-19 dose, i.e. the greatest extent to which a person will be ready to offer for procuring a COVID-19 vaccine, is a vital yardstick to assess the population's attitude towards out-of-pocket expenditure (OOPE) for the COVID-19 vaccine for themselves as well as for their children. To the best of our knowledge, there is no study assessing WTP for COVID-19 vaccination in India. The objective of our study was to determine how much money an individual attending a tertiary care centre (TCC) in West Bengal, India, would be willing to pay for a COVID-19 vaccine for themselves and their children (when it would be available) and the factors determining it.
| Methods|| |
Study design and participants
Following Ethical Approval from the Institutional Ethics Committee of the All India Institute of Medical Sciences, Kalyani, India (Ref.No.IEC/AIIMS/Kalyani/2021-004 issued 8th January, 2021), data were collected between July and August 2021. All adult (aged ≥18 years) individuals visiting the outpatient department (OPD) during this period were eligible to participate in this hospital-based cross-sectional analytical study.
The study was conducted at the OPD of a government TCC in suburban West Bengal, India. Daily, around 200 patients attend the OPD of the TCC, established in 2019. The study was conducted when there was an inadequate supply of COVID-19 vaccines in the state, and no COVID-19 vaccination centre (CVC) was available within a 15 km radius of the TCC. By June 2021, the total number of cases reported in the state and country were around 1.5 million and 30 million, respectively.
Using a systematic random sampling technique, every fifth individual was approached.
Using Cochran's sample size formula for continuous data.
N (sample size) = (z*σ/d)2
z = abscissa of the normal curve that cuts off an area α at the tails, usually set at 1.96 (95% confidence level)
σ = the standard deviation (SD) of an attribute in the population, ₹ (INR) 3709.2 (Harapan et al., converted from US$ 49.8)
d = desired level of precision for mean (₹ 4263.8 [Harapan et al., converted from $ 57.2]) 4.5% of mean (4263.8) = ₹191.9
N = (1.96 * 3709.2/191.9)2 = 1435. Assuming a non-response rate of 10%, the estimated sample size required was 1594 (1435 * 100/(100-10)).
Six nursing officers (NOs) conducted the personal interviews, and data were collected using EpiCollect version 5.0. During a 5-day training conducted by the authors (TR and FA), they also role-played the bidding game (BG) and open-ended (OE) question methods to ensure uniformity in participants' WTP quotations. If a patient visited alone, they were approached to check for eligibility. If attendees accompanied the patient, only one participant among the patient and attendees was included in the study using a lottery method. If the fifth individual was ineligible, the next person standing in the queue was approached. Data were collected using standard precautions in a separate kiosk after the individuals attending the OPD building were screened for COVID-19 symptoms and were registered for their OPD visit. The participants were contacted only once for the study, and data collection happened five times a week.
CVM was chosen over DCM since this public good (COVID-19 vaccine) was already available in the market, and it would judiciously appraise the participant's WTP by minimising the hypothetical bias. CVM was even more appropriate because COVID-19 vaccination for children is still not recommended in India, and adult vaccination was unavailable in our newly established TCC. Although various approaches under CVM to elicit WTP values, there is no general agreement on which is the most accurate technique. The payment scale may prejudice the respondent's opinion and the dichotomous choice WTP approach overestimates actual WTP. Although OE CVM suffers from the disadvantage of unworkable or no response, it provides the most accurate estimates of WTP. It reduces starting point bias if a respondent has accepted to pay. Hence, we combined BG and OE methods to estimate the WTP values. The BG approach was preferred since it was more reliable than other methods. It was anticipated to have content validity in India, where price negotiation for most goods is typical. The study assumed that a safe and fully-protected vaccine against COVID-19 was available for all ages. We considered inoculation with even a single dose of the COVID-19 vaccine as vaccination.
Socio-demographic, behavioural and comorbidity details were asked in the first section of the questionnaire. The second part consisted of participant WTP and the valuation for their vaccination. First, they were informed that most COVID-19 vaccines had 70%–90% efficacy. Then, NOs had a 'cheap talk' to prevent inflated and exaggerated responses. Since there is always a natural human inclination to overvalue WTP, the participants were explained and asked to answer the contingent options as if the fee was genuine and specific. They were requested to view the payment to be authentic and believable.
Then, the NOs simulated an auction process. Questions 'Imagine that if COVID-19 vaccine is available in this hospital, what is the maximum amount that you are willing to pay for COVID-19 vaccination (in Rupees)?' and 'Imagine that if COVID-19 vaccine is available in this hospital, what is the maximum amount that you are willing to pay for the next dose of COVID-19 vaccination (in Rupees)?' were directed to the unvaccinated and vaccinated, respectively. NOs first offered a starting price and asked the participants if they were willing to pay. The amount was increased or decreased each time the respondent accepted or rejected the initial bid [Figure 1]. The BG persisted till the respondent received a request. Then, NOs mentioned the last two offers and asked the participants for the maximum amount they were willing to pay (OE question). The opening offer was constant and kept at ₹250 (equivalent to US-$ 3.36, using a July 2021 exchange rate) like in private hospitals, even though it was free in government facilities.
|Figure 1: Bidding algorithm (in ₹) to elicit WTP value for COVID-19 vaccine. WTP: Willingness-to-pay, COVID-19: Coronavirus disease-2019|
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The third section was only for the participants who are parents of children aged <18 years. The same cheap talk and CVM techniques were described above with the question, 'What is the maximum amount you are willing to pay for your child's COVID-19 vaccination (in Rupees)?'
The questionnaire was translated into the vernacular (Bengali) and cross-checked by translating back to English. It was pretested in 50 individuals and modified accordingly.
A Chi-squared test was performed to check for the baseline differences in the two groups (unvaccinated and vaccinated). Participants' WTP was the maximum price expressed in the OE question. This outcome variable was described as a median and interquartile range (IQR) as it did not follow a normal distribution. We calculated the cumulative proportion of respondents with WTP for each price and plotted it in a graph to study the demand for the COVID-19 vaccine. Mann–Whitney U and Kruskal–Wallis tests compared the WTP between two and more than two groups, respectively. P < 0.05 was considered statistically significant. Data were analysed using the Stata version 14 (Stata Corp, College Station, TX, USA).
| Results|| |
A total of 1594 eligible individuals were contacted, of which 1565 were included in the study. All the participants were initially unfamiliar with the WTP methodology. Five and seven individuals refused to answer because they found the questions too complicated and did not want to attach a price to the benefits of vaccination, respectively. The rest 17 individuals refused to participate, citing they were hurrying to meet their physician, making the overall response rate 98.2%.
The socio-demographic and morbidity characteristics of the study participants are described in [Table 1]. The mean (SD) age was 40.8 (12.2) years, with 46.5% (n = 727) being male. Of total, 50.0% (n = 783) had completed secondary (Class 12) school, 66.0% (n = 1033) were from rural areas and 30.9% (n = 483) belong to upper-middle socioeconomic class as per modified BG Prasad scale. Of total, 70.4% (n = 1102) were parents to children aged <18 years. Regarding comorbidities, 19.8% (n = 310) and 15.0% (n = 234) of the participants were presently taking medication for hypertension and diabetes, respectively. Of the total, 5.1% (n = 79) reported ever being reverse transcription-polymerase chain reaction (RT-PCR) and/or rapid antigen test (RAT) positive (before vaccination) for COVID-19. Of the total vaccinated, 12 (1.54%) reported ever being RT-PCR or RAT positive after COVID-19 vaccination.
|Table 1: Socio.demographic and morbidity characteristics among adults attending a tertiary care centre in India, 2021 (n=1565)|
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Of the 1565 individuals, 50.2% (n = 785) were not vaccinated against COVID-19. The vaccinated and unvaccinated groups were significantly different in age, sex, education, occupation, residence, Socio-economic status (SES), hypertension and diabetes [Table 1]. Compared to the vaccinated group, the unvaccinated group comprised 26.0% (vs. 14.2%) individuals in the age category of 18–29 years, 60.0% (vs. 47.1%) females, and individuals with 13.8% (vs. 25.9%) hypertension and 11.3% (vs. 18.6%) diabetes.
Willingness-to-pay for oneself
[Figure 2] shows the cumulative proportion of participants willing to pay a given price for a COVID-19 first dose and subsequent/booster dose among unvaccinated (n = 785) and vaccinated (n = 780) individuals, respectively. The hypothetical demand for vaccination drops quickly when asked to pay for it; then, it falls gradually as the price increases with no overlap between the two curves for WTP. The proportion of respondents willing to be vaccinated against COVID-19 decreased from 100% when free to 35.3% (n = 277) and 45.0% (n = 351) when OOPE was required for the first dose and subsequent/booster dose, respectively. The overall median (IQR) WTP amount for the first dose of any COVID-19 vaccination among the unvaccinated participants was ₹0 (0–100), and the subsequent/booster dose among vaccinated was ₹0 (0–200). The median (IQR) WTP amount for the first dose among the willing to pay unvaccinated participants was ₹200 (100–300), and the subsequent/booster dose among ready-to-pay vaccinated participants was ₹200 (100–400) [Supplementary Figure 1]. On average, the WTP among unvaccinated was significantly lower than the WTP among vaccinated P < 0.01, [Figure 2].
|Figure 2: Relationship between the presented vaccine price and the cumulative proportion of participants who were willing to pay for a COVID-19 first dose and subsequent/booster dose among unvaccinated (n = 785) and vaccinated (n = 780) individuals, respectively attending a tertiary care centre in India, 2021 (n = 1565). COVID-19: Coronavirus disease-2019|
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Willingness-to-pay for children
Similarly, [Figure 3] shows the cumulative proportion of participants willing to pay for their children's COVID-19 vaccination among unvaccinated (n = 509, 64.8%) and vaccinated (n = 593, 76.0%) parents. When asked to pay for the vaccine, the hypothetical demand for vaccination drops less quickly compared to [Figure 2]. The demand falls gradually with considerable overlap between the two curves for WTP (P = 0.54). The proportion of parents willing to pay for their children's COVID-19 vaccination decreased from 100% when free to 55.4% (282/509) and 50.1% (297/593) when OOPE was required among the unvaccinated and vaccinated groups, respectively. In both groups, the overall median (IQR) WTP for vaccinating children with a hypothetical first dose of any COVID-19 vaccination was ₹50 (0–300). The median (IQR) WTP amount for vaccinating their children among the unvaccinated but willing-to-pay-for-children parents was ₹300 (100–500) and among the vaccinated and willing-to-pay-for-children parents was ₹300 (150–550) [Supplementary Figure 1].
|Figure 3: Relationship between the presented vaccine price and the cumulative proportion of participants who were willing to pay for their children's COVID-19 vaccination among unvaccinated (n = 509) and vaccinated (n = 593) parents attending a tertiary care centre in India, 2021 (n = 1102). COVID-19: Coronavirus disease-2019|
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Details regarding the WTP values of the subgroups willing to pay and the flowchart of participant enrolment are given in the supplementary file [Supplementary Figure 1]. Socio-demographic and morbidity characteristics of the parents in both the vaccinated and unvaccinated groups are also provided in the additional file [Table S1].
Factors influencing willingness-to-pay
Among the vaccinated individuals, significant differences were found in their WTP prices for subsequent/booster dose regarding age category (P = 0.02), sex (P = 0.03), education (P < 0.01), occupation (P < 0.01), residence (P < 0.01) and SES (P < 0.01). Among the unvaccinated individuals, significant differences were found in their WTP prices for the first dose regarding age category (P = 0.02), education (P < 0.01) and SES (P < 0.01).
| Discussion|| |
The present study reports the median (IQR) WTP amount for the first dose of the COVID-19 vaccine and subsequent/booster dose among the unvaccinated and vaccinated individuals attending a tertiary care hospital in India were ₹0 (0–100) and ₹0 (0–200), respectively. The participating parents were willing to pay ₹50 (0–300) on average for their children whenever the government declared the vaccines safe. We also found that age, education level and SES determined the WTP price for a COVID-19 vaccine.
The findings of this study have revealed the people's valuation of risk for themselves and their children in an Indian setting. In the present study, the median WTP amount among the participants who wanted to pay for the COVID-19 vaccine was not higher than ₹400 (US$ 5), as compared to the studies conducted in similar study settings., However, more than half of the study participants had expressed unwillingness to pay for the COVID-19 dose in both the vaccinated and unvaccinated groups. The proportion of unwillingness to pay for a vaccine was higher among those not inoculated than those who had already received a dose of the vaccine. On the contrary, studies conducted in other countries reported more WTP and much higher average WTP prices for COVID-19 vaccines than ours., In India, vaccines are divided into Universal Immunisation Programme (UIP) and non-UIP vaccines, depending on the financing mechanism for immunisation. The children aged 0–14 years receive vaccines under UIP free of cost from public health-care systems. The non-UIP vaccines, like adult vaccines, are paid out-of-pocket without any subsidy, resulting in meagre coverage rates of non-UIP vaccines in India. Most of our study participants were from rural backgrounds with no OOPE for UIP vaccines. Thus, the perception that the vaccine programme is the government's responsibility and must be given free of cost might have played some role in expressing WTP in our study population.
The general population has been inundated with COVID-19 vaccine importance, and most of the people in LMIC are keen and motivated to get vaccinated after witnessing its health benefits. However, the obstacle in LMICs, like in India, is vaccine availability and the affordability of the price tag. Consequently, OOPE may become the only choice available. When vaccines are in limited supply, policy-makers need to prioritise and allocate them to inoculate people who are more prone and capable of silently spreading SARS-CoV-2. The community will benefit by vaccinating the people who cannot afford to stay back or work from home. We also tend to forget the costs like travel and loss of wages associated with receiving a vaccination for the low-income group section of our society. We found SES to be significantly associated with WTP price, like in previous studies globally.,,,,, The inherent property of vaccines possessing 'positive externality' aids in this decision of vaccine distribution methodologically based on an individual's SES. The same policy will apply to the injection of children of low or low-middle SES families. To promote herd immunity, all sections of society should be vaccinated. India is not far from achieving the World Health Organisation's target of vaccinating 40% of the country's population by the end of 2021. This is only possible if the prices are kept within reach of the more common. Designating more CVCs in private and public sectors with economical pricing of vaccines will promote vaccine equity, which will assist in terminating the pandemic.
We also found that study participants who had already received a dose of the COVID-19 vaccine were more willing to pay than those who did not receive the vaccine. An earlier study reported that a person who had received an adult vaccine shows more willingness to get the COVID-19 vaccine. The observation can explain that WTP for any recent or unfamiliar vaccine is affected by a person's preconceived perspective regarding the disease. Thus, it is difficult to predict if the general public will buy and receive a new COVID-19 vaccine, even though proven to be harmless and productive.
The vaccinated study participants in the present study had a high proportion of older adults and graduates. The role of age,, and education in accepting and paying for the COVID-19 vaccine has been found in earlier studies. Hence, age and university degree might be more strongly linked to health literacy and level of awareness generation. Since people with higher education understand the value of vaccination, they are more likely to pay for it.
Even though the participants expressed a lesser willingness to pay for their vaccine, they showed a higher willingness to pay to vaccinate their children. They also said paying an even higher amount for the vaccination of their children. The increasing WTP when children are involved may be due to paternal altruism towards children. This finding aligned with another study in the USA by Catma and Reindl.
The present study is cross-sectional, so causality for the factors could not be established. Findings from a government hospital-based study, where the cost of treatment is subsidised, may not hold for the general population. Finally, the expectations of a fully funded vaccine may have impacted the respondents' stated preferences and enhanced the social desirability bias.
The study findings showed that people are not willing to commit financially to their vaccination but are eager to pay ₹50 for their children's COVID-19 vaccination when available. This points out that GoI should continue providing free vaccines to low-income groups and let the higher socio-economic classes acquire them for a fee. However, the very low WTP in the present study indicates that the vaccine cost of ₹250 available in private health-care facilities must be subsidised even more. The role of socio-demographic factors needs to be examined before announcing the price of one dose of the COVID-19 vaccine for adults and children. A further comprehensive community-based cost-benefit study will help policy-makers decide the affordable amount of the vaccine for all sections and age groups of the Indian population. Appropriate health communication interventions for vaccine safety and importance among adolescents and children are required for enhancing the vaccination drive to attain herd immunity against SARS-CoV-2 infection.
| Conclusion|| |
The magnitude of WTP for the COVID-19 vaccine was low for themselves but was higher for their children among individuals attending a hospital. Policy-makers should consider income, education and age to cap the private-sector vaccination price.
The authors would like to thank the nursing officers who helped us with this study.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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[Figure 1], [Figure 2], [Figure 3]