Characteristics of respondents
Table
1 shows the distribution of the respondents by socio-demographic characteristics of mothers and child. Majority of the mothers were between the ages of 30 to 39 years (83%) with median age of 34 years. Most of the respondents were Malay (68.3%) and Muslim (69.7%). A large proportion of the respondents were married, constituting 98.4% of the total respondents whereas the remaining 1.6% was single, divorced or widowed. More than half of the respondents (89.4) had attained tertiary level education of bachelor’s degree and above. In this study, majority of the mothers, 88.9%, were working while the rest, 11.1%, were not working. For family composition, 88.1% of respondents belonged to a family of 5 and below members. Most respondents (36.9%) reported had 2 children. For child factors, a large proportion of the children (79.5) were 2 years or above. The median age for the children was 40 months (IQR: 23). Besides that, nearly half of the children, 494 (48.7%) were male. The highest percentage of the participating children (36.9%) was in the birth order of second.
Table 1
Distribution of respondents by socio-demographic characteristic, child factors and healthcare factors (N = 1015)
Socio-demographic characteristics |
Mother’s age (years) |
20 to 29 | 107 | 10.5 |
30 to 39 | 842 | 83.0 |
40 and above | 66 | 6.5 |
Ethnicity |
Malay | 693 | 68.3 |
Chinese | 188 | 18.5 |
Indian | 119 | 11.7 |
Othersa | 15 | 1.5 |
Religion |
Muslim | 707 | 69.7 |
Buddhist | 160 | 15.8 |
Hindu | 100 | 9.9 |
Christian | 45 | 4.5 |
Othersb | 3 | 0.3 |
Marital Status |
Married | 999 | 98.4 |
Single/Divorced/Widowed | 16 | 1.6 |
Educational Level |
Secondary school | 28 | 2.8 |
Pre-university | 13 | 1.3 |
Certificate or Diploma | 67 | 6.6 |
Bachelor’s Degree | 696 | 68.6 |
Postgraduate studies | 211 | 20.8 |
Working Status |
Working | 902 | 88.9 |
Not-working | 113 | 11.1 |
Family Composition |
5 and below | 894 | 88.1 |
Above 5 | 121 | 11.9 |
Number of Children |
1 | 359 | 35.4 |
2 | 375 | 36.9 |
3 and above | 281 | 27.7 |
Child Factors |
Child’s Age |
2 years and below | 208 | 20.5 |
Above 2 years | 807 | 79.5 |
Child’s Gender |
Male | 494 | 48.7 |
Female | 521 | 51.3 |
Child’s Birth Order |
First | 359 | 35.4 |
Second | 375 | 36.9 |
Third and above | 281 | 27.7 |
Healthcare Factors |
Place of Immunization |
Government clinic | 639 | 63.0 |
Government hospital | 77 | 7.6 |
Private clinic | 330 | 32.5 |
Private hospital | 148 | 14.6 |
Distance to health facility (km) |
1 to 5 | 580 | 57.1 |
6 to 10 | 253 | 24.9 |
More than 10 | 182 | 17.9 |
Travelling time (minutes) |
Less than 15 | 461 | 45.4 |
15 to 29 | 378 | 37.2 |
30 and above | 176 | 17.3 |
Waiting time (minutes) |
Less than 60 | 348 | 34.3 |
60 to 119 | 329 | 32.4 |
120 and above | 338 | 33.3 |
Delayed immunization schedule |
Yes | 210 | 20.7 |
No | 805 | 79.3 |
The distribution of respondents according to place of immunization indicated that more than half of the respondents, 63%, immunize their children mainly in government clinic. As for the distance to the preferred immunization health facility, 57.1% of the participating mothers reported a distance of 1 to 5 km (57.1%) with a median distance of 5 km (IQR 7 km). Nearly half of the total respondents travelled less than 15 min to the regularly visited immunization health facility (45.4%). The median travelling time was 15 min (IQR 10). Particularly, 34.1% of the mothers reported that they waited less than 60 min with a median time of 60 min (IQR 90). Amongst all the 1015 children, 20.7% of them have delayed their immunization schedule by over 30 days for at least one dose of immunization and the rest had received all the recommended immunizations within 1 month of due date (79.3%).
Prevalence of childhood immunization
The prevalence of childhood immunization among children aged 5 years and below attending child care centers in Petaling District was 20.7% for defaulters and 79.3% for non-defaulters. From the 210 respondents in the defaulter group, DTaP/IPV/Hib booster dose was most frequently defaulted in 131 (62.4%) children, followed by DTaP/IPV/Hib third dose in 124 (59%) children. Among the doses of Hepatitis B immunization, the third dose had the most defaulters (22.4%) followed by the second dose (10.5%) while the least rate of defaulters was for the first dose (4.8%). The rate of defaulters for MMR immunization was 24.3%. In addition, 15 children had not received BCG immunization against tuberculosis (Table
2).
Table 2
Distribution of defaulters according to types of immunization (n = 210)
BCG | Birth | 15 | 7.1 |
Hepatitis B – 1st dose | Birth | 10 | 4.8 |
Hepatitis B – 2nd dose | 1 | 22 | 10.5 |
Hepatitis B – 3rd dose | 6 | 47 | 22.4 |
DTaP/IPV/Hib 1st dose | 2 | 84 | 40.0 |
DTaP/IPV/Hib 2nd dose | 3 | 100 | 47.6 |
DTaP/IPV/Hib 3rd dose | 5 | 124 | 59.0 |
MMR | 12 | 51 | 24.3 |
DTaP/IPV/Hib booster dose | 18 | 131 | 62.4 |
Table
3 shows the factors associated with immunization defaulters. The results show that there was a significant association between immunization defaulters and maternal age (χ2 = 18.811,
df = 2,
p < 0.0001), ethnicity (χ2 = 22.325,
df = 1,
p < 0.0001) and religion (χ2 = 14.096,
df = 1,
p < 0.0001). According to age group, the mothers in the older group tend to have higher percentage of defaulters. Between ethnicity and religion, there were more defaulters among the Non-Malay and Non-Muslim group respectively. Among mothers living without partners such as those who were singled, divorced or widowed, 81.3% of them were found in the defaulter group, whereas only 18.8% of them were found in the non-defaulter group and this difference was statistically significant (Fisher Test
p < 0.0001).
Table 3
Factors associated with immunization defaulters (N = 1015)
Mother’s age (years) |
20 to 29 | 25 (23.4) | 82 (76.6) | < 0.0001* |
30 to 39 | 158 (18.8) | 684 (81.2) | |
40 and above | 27 (40.9) | 39 (59.1) | |
Ethnicity |
Malay | 115 (16.6) | 578 (83.4) | < 0.0001* |
Non-Malay | 95 (29.5) | 227 (70.5) | |
Religion |
Muslim | 124 (17.5) | 583 (82.5) | < 0.0001* |
Non-Muslim | 86 (27.9) | 222 (72.1) | |
Marital status |
Married | 197 (19.7) | 802 (80.3) | < 0.0001*+ |
Single/divorcee/widow | 13 (81.3) | 3 (18.8) | |
Educational level |
Diploma and below | 47 (43.5) | 61 (56.5) | < 0.0001* |
Degree and above | 163 (18.0) | 744 (82.0) | |
Working status |
Working | 175 (19.4) | 727 (80.6) | 0.004* |
Not-working | 35 (31.0) | 78 (69.9) | |
Family composition |
5 and below | 168 (18.8) | 726 (81.2) | < 0.0001* |
Above 5 | 42 (34.7) | 79 (65.3) | |
Number of children |
1 to 2 | 129 (17.6) | 605 (82.4) | < 0.0001* |
3 to 4 | 72 (27.6) | 189 (72.4) | |
5 or higher | 9 (45.0) | 11 (55.0) | |
Child’s age |
2 years and below | 56 (26.9) | 152 (73.1) | 0.013* |
Above 2 years | 154 (19.1) | 653 (80.9) | |
Child’s gender |
Male | 116 (23.5) | 378 (76.5) | 0.032* |
Female | 94 (18.0) | 427 (82.0) | |
Child’s birth order |
First born | 52 (14.5) | 307 (85.5) | < 0.0001* |
Non-first born | 158 (24.1) | 498 (75.9) | |
Place of immunization |
Government | 102 (17.9) | 468 (82.1) | 0.042* |
Private | 84 (24.7) | 256 (75.3) | |
Mixed | 24 (22.9) | 81 (77.1) | |
Distance to health facility (km) |
1 to 5 | 98 (16.9) | 482 (83.1) | 0.001* |
More than 5 | 112 (25.7) | 323 (74.3) | |
Travelling time to health facility (minutes) |
Less than 15 | 63 (13.7) | 398 (86.3) | < 0.0001* |
15 to 29 | 96 (25.4) | 282 (74.6) | |
30 and above | 51 (29.0) | 125 (71.0) | |
Waiting time (minutes) |
Less than 60 | 83 (23.9) | 265 (76.1) | 0.199 |
60–119 | 63 (19.1) | 266 (80.9) | |
120 and above | 64 (18.9) | 274 (81.1) | |
Delayed immunization schedule |
Yes | 84 (40.0) | 126 (60.0) | < 0.0001* |
No | 126 (15.7) | 679 (84.3) | |
Maternal highest educational level was also found to have a statistically significant association with immunization defaulters (χ2 = 38.386, df = 1, p < 0.0001). Specifically, 43.5% of mothers with diploma and below educational background had defaulted on their children’s immunization compared to 18.0% of mothers who completed at least bachelor’s degree or postgraduate studies. Mother’s working status also showed a significant difference between the two groups in which 31.0% of mothers who were not working defaulted compared to 19.4% of working mothers defaulted (χ2 = 8.195, df = 1, p = 0.004). The difference between immunization defaulters of children belonging to a larger family size of more than 5 members and smaller family size with at least 5 members or less found to be significant (χ2 = 16.459, df = 1, p < 0.0001). A significant association was found between the number of children within the family with immunization defaulters (χ2 = 19.108, df = 2, p < 0.0001). The more number of children within a family, the higher the percentage of immunization defaulters.
Besides, the result also shows that there was a significant association between childhood immunization defaulters and child’s age (χ2 = 6.195, df = 1, p = 0.013), gender (χ2 = 4.572, df = 1, p = 0.032) and birth order (χ2 = 13.033, df = 1, p < 0.0001). The result also shows that place of immunization (χ2 = 6.356, df = 2, p = 0.042), distance (χ2 = 11.866, df = 1, p = 0.001), travelling time (χ2 = 26.331, df = 2, p < 0.0001) and delayed immunization schedule (χ2 = 60.171, df = 1, p < 0.0001) were found to have significant association with immunization defaulters. However, there was no significant association observed between the waiting time to get the child immunized and childhood immunization (p > 0.05).
In the binary regression logistic analysis, independent variables that were possibly associated with childhood immunization defaulters were entered into the logistic regression model. There was no multicollinearity; and there was no significant interaction between the variables. The variables that were retained in the final logistic regression model were religion, educational level, number of children, child’s age group, travelling time to health facility and delayed immunization schedule.
Table
4 presents the results of binary logistic regression to determine the predictors of childhood immunization defaulters. The predictors of childhood immunization defaulters were non-Muslims (adjusted OR = 1.669, 95% CI = 1.173, 2.377,
p = 0.004), mothers with diploma and below educational background (adjusted OR = 2.296, 95% CI = 1.460, 3.610,
p < 0.0001), multiple children of 5 and above in a family (adjusted OR = 2.656, 95% CI = 1.004, 7.029,
p = 0.040), mothers with younger children aged 2 years and below (adjusted OR = 1.700, 95% CI = 1.163, 2.486,
p = 0.006), long travelling time of more than 30 min to the immunization health facility (adjusted OR = 2.303, 95% CI = 1.474, 3.599,
p < 0.0001) and delayed at least one of the immunization schedule (adjusted OR = 2.747, 95% CI = 1.918, 3.933,
p < 0.0001).
Table 4
Binary logistic regression analysis of predictors of immunization defaulters
Religion |
Muslim | 1 | | |
Non-Muslim | 1.669 | 1.173–2.377 | 0.004* |
Educational Level |
Diploma and below | 2.296 | 1.460–3.610 | 0.011* |
Bachelor’s degree and above | 1 | | |
Number of Children |
1 to 2 | 1 | | |
3 to 4 | 1.599 | 1.109–2.307 | 0.012* |
5 or higher | 2.656 | 1.004–7.029 | 0.040* |
Child’s Age |
2 years and below | 1.700 | 1.163–2.486 | 0.006* |
Above 2 years | 1 | | |
Travelling time to health facility (minutes) |
Less than 15 | 1 | | |
15–29 | 1.811 | 1.247–2.628 | 0.002* |
30 and above | 2.303 | 1.474–3.599 | < 0.0001* |
Delayed immunization schedule |
Yes | 2.747 | 1.918–3.933 | < 0.0001* |
No | 1 | | |
The significance levels of the Wald statistics demonstrated that all the 6 predictor variables made a significant contribution to immunization defaulters after adjusting other variables. The Hosmer-Lemeshow test showed a p-value of 0.421 which means that it is not statistically significant, implying that the logistic regression model was statistically significant and fits the sample (χ2 = 7.078, df = 7, p = 0.421). This study found that those factors can explain 16.6% of the variation in the factors influencing immunization defaulters.