Ann Clin Microbiol 2025;28(4):20. Factors influencing microbial diagnostic testing for infectious diseases in Korea: a nationwide retrospective cohort study

Table 2. Factors affecting bacterial culture and antimicrobial susceptibility tests: multivariate analysis
CharacteristicsVariatesPneumoniaBloodstream infectionUrinary tract infectionSoft tissue infection
Total (n)Incidence rate (%)OR95% CIP-valueTotal (n)Incidence rate (%)OR95% CIP-valueTotal (n)Incidence rate (%)OR95% CIP-valueTotal (n)Incidence rate (%)OR95% CIP-value
SexMale1,158,2884.501787,4103.0611,181,5804.5912,965,68911.521
Female1,331,5305.190.7890.782 – 0.796<0.00011,177,5624.590.8560.840 – 0.872<0.00012,827,98211.021.4401.426 – 1.455<0.00014,439,66517.290.7810.773-0.789<.0001

Age (yr)

≤ 19878,49610.771369,5174.531363,0214.4511,034,28512.681
20-29154,4222.330.2450.237 – 0.254<0.0001218,8163.300.1480.139 – 0.158<0.0001345,3495.210.2690.263 – 0.276<0.0001813,36712.280.7750.747-0.804<0.0001
30-39196,2142.830.2750.267 – 0.283<0.0001225,6913.260.1540.146 – 0.163<0.0001433,1556.260.2180.213 – 0.224<0.0001885,66212.790.7290.705-0.754<0.0001
40-49216,5752.650.3060.299 – 0.314<0.0001233,9562.860.1930.184 – 0.203<0.0001522,2786.390.2370.232 – 0.242<0.0001972,17411.890.7320.71-0.755<0.0001
50-59232,6892.700.3510.344 – 0.358<0.0001279,9903.250.2200.211 – 0.229<0.0001698,1138.100.2650.260 – 0.270<0.00011,175,66613.640.7850.762-0.807<0.0001
60-69307,5084.240.4150.407 – 0.422<0.0001298,5484.120.2830.273 – 0.294<0.0001762,45110.520.2960.291 – 0.302<0.00011,219,78716.830.9490.923-0.9760.6523
70-79256,7907.110.6150.604 – 0.626<0.0001202,8985.620.4080.393 – 0.424<0.0001529,27814.660.4100.402 – 0.418<0.0001808,47822.401.3101.273-1.347<0.0001
≥ 80247,12412.031.2181.197 – 1.239<0.0001135,5566.600.5860.565 – 0.609<0.0001355,91717.330.8210.806 – 0.836<0.0001495,93524.151.6721.625-1.721<0.0001

Insurance quintile

Medical benefits117,8857.74195,8966.301189,33512.441317,29420.841
1st500,4684.950.8240.808 – 0.8390.0011407,3364.030.9240.892 – 0.9580.4517874,0668.650.7690.754 – 0.784<0.00011,566,00315.500.7650.750-0.780<0.0001
2nd404,5823.870.8450.829 – 0.8610.0337362,3973.470.9370.903 – 0.9730.0406742,2537.110.7820.767 – 0.7980.44511,398,00413.380.8000.784-0.8160.6651
3rd624,2734.940.8260.811 – 0.8410.0039460,5703.650.9230.890 – 0.9560.5587915,7747.250.7600.745 – 0.775<0.00011,737,60013.760.7650.750-0.780<0.0001
4th842,6105.010.710.698 – 0.723<0.0001638,7733.800.8140.787 – 0.842<0.00011,288,1347.660.6530.641 – 0.665<0.00012,386,45314.200.6920.679-0.704<0.0001

Residential area

Region 3880,3015.441621,5683.8411,300,3198.0412,367,80414.641
Region 2606,7514.710.9580.947 – 0.968<0.0001469,7023.640.8850.863 – 0.906<0.0001993,6197.710.9250.914 – 0.9360.04851,770,90513.730.9890.976-1.003<0.0001
Region 11,002,7664.201.0201.010 – 1.030<0.0001873,7023.660.9630.943 – 0.9830.01661,715,6247.190.8370.828 – 0.846<0.00013,266,64513.690.9090.898-0.919<0.0001
DisabilityNo  1  1  1  1
Yes  1.5091.490 – 1.528<0.0001  1.3871.354 – 1.421<0.0001  1.4701.450 – 1.490<0.0001  1.6851.663-1.706<0.0001

Disease severity (CCI)

0  1  1  1  1
1  1.4611.442 – 1.48<0.0001  0.9920.963 – 1.023<0.0001  1.0361.022 – 1.050<0.0001  1.4021.372-1.433<0.0001
2  1.5461.519 – 1.574<0.0001  1.3201.272 – 1.371<0.0001  1.1541.135 – 1.174<0.0001  1.7591.718-1.801<0.0001
≥ 3  1.8551.823 – 1.887<0.0001  1.7721.712 – 1.834<0.0001  1.3401.319 – 1.362<0.0001  3.3403.267-3.415<0.0001

Type of medical institutions

Senior general hospitals  1  1  1  1
General hospitals  0.8350.824 – 0.846<0.0001  0.3770.368 – 0.386<0.0001  0.9120.900 – 0.924<0.0001  0.6280.618-0.638<0.0001
Hospitals  0.4620.455 – 0.469<0.0001  0.0770.074 – 0.080<0.0001  0.4810.473 – 0.489<0.0001  0.5130.502-0.523<0.0001
Clinics  0.0650.064 – 0.066<0.0001  0.0100.010 – 0.011<0.0001  0.0800.079 – 0.082<0.0001  0.1970.195-0.200<0.0001
Nursing hospital  0.7000.685 – 0.715<0.0001  0.7840.761 – 0.808<0.0001  0.7270.704 – 0.751<0.0001  1.2431.210-1.277<0.0001
Othersa)  0.1370.117 – 0.161<0.0001  0.0230.017 – 0.031<0.0001  0.1360.122 – 0.152<0.0001  0.3510.324-0.380<0.0001

Chemotherapy in solid cancer

No  1  1  1  1
Yes  1.3581.328 – 1.389<0.0001  1.7511.686 – 1.819<0.0001  0.9550.931 – 0.9790.0003  1.8981.858-1.940<0.0001

Hematologic malignancy

No  1  1  1  1
Yes  1.7821.711 – 1.856<0.0001  1.8391.730 – 1.954<0.0001  1.1821.118 – 1.250<0.0001  1.8871.809-1.968<0.0001

Organ transplantation

No  1  1  1  1
Yes  1.5851.504 – 1.67<0.0001  1.3961.283 – 1.518<0.0001  1.6641.575 – 1.758<0.0001  2.0291.940-2.122<0.0001
HIV infectionNo  1  1  1  1
Yes  0.8550.747 – 0.9800.0243  0.5360.418 – 0.688<0.0001  0.5150.432 – 0.615<0.0001  0.8330.723-0.9600.0117
DiabetesNo  1  1  1  1
Yes  0.8990.889 – 0.909<0.0001  0.9090.889 – 0.930<0.0001  0.9420.932 – 0.953<0.0001  2.6132.573-2.654<0.0001

Alcoholic dependence

No  1  1  1  1
Yes  2.0882.001 – 2.179<0.0001  1.6921.562 – 1.832<0.0001  1.8451.759 – 1.935<0.0001  1.7121.642-1.785<0.0001
MalnutritionNo  1  1  1  1
Yes  1.9271.883 – 1.971<0.0001  1.8281.754 – 1.906<0.0001  1.6981.651 – 1.746<0.0001  1.7651.717-1.815<0.0001

Steroid treatment

No  1  1  1  1
Yes  1.2271.216 – 1.237<0.0001  0.9110.894 – 0.928<0.0001  1.0931.083 – 1.104<0.0001  1.1411.130-1.153<0.0001
PregnancyNo            1     
Yes            0.7120.685 – 0.740<0.0001     
Necrotizing fasciitisNo                 1
Yes                 13.2111.912-14.649<0.0001
Pyogenic arthritisNo                 1
Yes                 3.213.097-3.328<0.0001
Clostridium muscle necrosisNo                 1
Yes                 9.7516.077-15.647<0.0001
Open wounds by bitesNo                 1
Yes                 1.1991.182-1.216<0.0001

Bold form: statistically significant.
a)Others included dental hospitals, healthcare centers, child health centers, and oriental medicine clinics.
Abbreviations: OR, odds ratio; CI, confidence interval; CCI, Charlson comorbidity index; HIV, human immunodeficiency virus.