Table 2. Characteristic differences of respondents in three subgroups by percentage levels of IgG (%) identified by cluster analysis (N = 1400).
| Characteristic | Cluster I N = 858 n (%) | Cluster II N = 362 | Cluster III N = 180 | ANOVA for continuous and χ2 for categorical variables P-value |
| Number of schools | 9 | 11 | 6 | |
| Mean (SD) percentage of IgG | 2.37(2.39) | 9.51(2.59) | 25.2(3.02) | <0.001 |
| Percentage range of IgG | 0 to 5.9 | 6.5 to 14.3 | 21.7 to 33.9 | |
| Personal background | ||||
| Age, years | ||||
| Mean age (SD) φ | 45.1(15.1) | 44.4(16.0) | 44.4(18.1) | ns |
| Gender | ||||
| Male | 280(32.6) | 110(30.4) | 55(30.6) | |
| Female | 578(67.4) | 252(69.6) | 125(69.4) | ns |
| Ethnicity¶ | ||||
| Malay | 523(61.3) | 209(58.1) | 158(88.3) | |
| Chinese | 151(17.7) | 107(29.7) | 13(7.3) | <0.001 |
| Indian | 179(21.0) | 44(12.2) | 8(4.5) | |
| Average household monthly income† | ||||
| <MYR2000 | 363(42.3) | 143(39.5) | 91(50.6) | |
| MYR2001-4000 | 433(50.5) | 198(54.7) | 72(40.0) | 0.027 |
| >MYR4000 | 62(7.2) | 21(5.8) | 17(9.4) | |
| Educational level | ||||
| No formal education | 51(5.9) | 19(5.2) | 5(2.8) | |
| Primary | 153(17.8) | 75(20.7) | 28(15.6) | |
| Secondary | 438(51.0) | 193(53.3) | 101(56.1) | ns |
| Tertiary | 216(25.2) | 75(20.7) | 46(25.6) | |
| Household size | ||||
| Mean (SD) number of householdsφ | 3.18(2.0) | 3.21(1.95) | 3.02(2.08) | ns |
| Self-reported house and surrounding environment | ||||
| House type | ||||
| High rise | 52(6.1) | 14(3.9) | 28(15.6) | <0.001 |
| Terrace house | 425(49.5) | 182(50.3) | 41(22.8) | |
| Single/village house | 381(44.4) | 166(45.9) | 111(61.7) | |
| Density of vegetation/plants | ||||
| None | 40(4.7) | 18(5.0) | 9(5.0) | |
| Low | 413(48.1) | 186(51.4) | 67(37.2) | |
| Moderate | 229(26.7) | 54(14.9) | 39(21.7) | <0.001 |
| A lot | 176(20.5) | 104(28.7) | 65(36.1) | |
| Locality | ||||
| Urban | 352(41.0) | 247(68.2) | 74(41.1) | |
| Suburban | 318(37.1) | 51(14.1) | 73(40.6) | <0.001 |
| Rural | 188(21.9) | 64(17.7) | 33(18.3) | |
| Health beliefs | ||||
| Perceived severity (scale 1–10) | ||||
| Mean (SD) severity scoreφ | 7.1(3.3) | 7.6(2.9) | 7.3(3.0) | 0.037 |
| Severity of dengue | ||||
| 1–2 | 158(18.4) | 41(11.3) | 24(13.3) | |
| 3–4 | 31(3.6) | 13(3.6) | 12(6.7) | |
| 5–6 | 69(8.0) | 42(11.6) | 20(11.1) | <0.001 |
| 7–8 | 191(22.3) | 34(9.4) | 38(21.1) | |
| 9–10 | 409(47.7) | 232(64.1) | 86(47.8) | |
| Perceived susceptibility (scale 1–10) | ||||
| Mean (SD) susceptibility scoreφ | 5.3(2.5) | 5.5(2.2) | 5.2(2.3) | ns |
| Susceptibility of dengue | ||||
| 1–2 | 162(18.9) | 49(13.5) | 31(17.2) | |
| 3–4 | 63(7.3) | 21(5.8) | 13(7.2) | |
| 5–6 | 363(42.3) | 193(53.3) | 88(48.9) | 0.037 |
| 7–8 | 207(24.1) | 69(19.1) | 34(18.9) | |
| 9–10 | 63(7.3) | 30(8.3) | 14(7.8) | |
| Perceived barriers to sustained prevention (scale 1–10) | ||||
| Mean (SD) barrier scoreφ | 4.2(2.6) | 4.6(2.5) | 3.7(2.6) | <0.001 |
| Barriers to sustained dengue prevention | ||||
| 1–2 | 292(34.0) | 95(26.2) | 81(45.0) | |
| 3–4 | 119(13.9) | 39(10.8) | 32(17.8) | |
| 5–6 | 281(32.8) | 164(45.3) | 36(20.0) | <0.001 |
| 7–8 | 125(14.6) | 44(12.2) | 21(11.7) | |
| 9–10 | 41(4.8) | 20(5.5) | 10(5.6) | |
| Self-efficacy | ||||
| Lack of self-efficacy in taking preventive measures | ||||
| Strongly agree/agree | 339(39.5) | 140(38.7) | 93(51.7) | |
| Strongly disagree/disagree | 519(60.5) | 222(61.3) | 87(48.3) | 0.007 |
| Cues to action | ||||
| Mosquito problem in neighbourhood | ||||
| None | 293(34.1) | 73(20.2) | 61(33.9) | |
| Low | 368(42.9) | 203(56.1) | 60(33.3) | |
| Moderate | 138(16.1) | 51(14.1) | 27(15.0) | <0.001 |
| Severe | 59(6.9) | 35(9.7) | 32(17.8) | |
| Neighbour with dengue fever | ||||
| Yes | 130(15.2) | 64(17.7) | 63(35.0) | |
| No | 728(84.8) | 298(82.3) | 117(65.0) | <0.001 |
| Frequency of fogging in neighbourhood | ||||
| None | 276(32.2) | 57(15.7) | 43(23.9) | |
| Rarely | 406(47.3) | 219(60.5) | 74(41.4) | |
| Occasionally | 125(14.6) | 52(14.4) | 24(13.3) | <0.001 |
| Often | 51(5.9) | 34(9.4) | 39(21.7) | |
| Lack of preventive measures at community level | ||||
| Strongly agree/agree | 362(42.2) | 161(44.5) | 96(53.3) | |
| Strongly disagree/disagree | 496(57.8) | 201(55.5) | 84(46.7) | 0.023 |
| Lack of preventive measures from authorities | ||||
| Strongly agree/agree | 245(28.6) | 117(32.3) | 47(26.1) | ns |
| Strongly disagree/disagree | 613(71.4) | 245(67.7) | 133(73.9) | |
| Practices | ||||
| Self-practices in prevention of mosquito breeding (0–36) | ||||
| Mean penalty points (SD) ‡ φ | 13.7(6.6) | 13.5(5.9) | 13.4(6.5) | ns |
| 0–12 | 409(47.7) | 164(45.3) | 91(50.6) | |
| 13–25 | 420(49.0) | 186(51.4) | 80(44.4) | ns |
| 26–36 | 29(3.4) | 12(3.3) | 9(5.0) | |
| Self-practices in prevention of mosquito bite (0–28) | ||||
| Mean penalty points (SD) ‡ φ | 21.3(6.9) | 16.6(9.8) | 20.9(6.9) | <0.001 |
| 0–10 | 92(10.7) | 124(34.3) | 18(10.0) | |
| 11–20 | 110(12.8) | 39(10.8) | 40(22.2) | |
| 21–28 | 656(76.5) | 199(50.0) | 122(67.8) | <0.001 |
| Knowledge (0–43) | ||||
| Mean knowledge score (SD) § φ | 27.6(7.6) | 26.5(8.4) | 29.2(6.7) | <0.001 |
| 0–14 | 50(5.8) | 44(12.2) | 5(2.8) | |
| 15–30 | 477(55.6) | 188(51.9) | 87(48.3) | <0.001 |
| 21–42 | 331(38.6) | 130(35.9) | 88(48.9) | |
¶
Other ethnic groups not included in analysis; number does not total 1400.
†
1 US Dollar = 3.0 Malaysian Ringgit (MYR).
‡
A higher score indicates decreasing preventive practices.
§
A higher score indicates increasing knowledge.
***Association is significant at the 0.001 level.
**Association is significant at the 0.01 level.
*Association is significant at the 0.05 level.
φ
One-way analysis of variance (ANOVA).