Volume 8, Number 7—July 2002
    
    Research
Time-Space Clustering of Human Brucellosis, California, 1973–1992 1
Table 2
Ederer-Myers-Mantel (EMM) procedure for time-space clustering of reported human brucellosis cases, California, 1973–1992
| Years | Population | County | California areaa | Chi square | p valueb | 
|---|---|---|---|---|---|
| 1973–1977 | Hispanic | Los Angeles | Southern California | 74.94 | <0.001 | 
| Orange | Southern California | 4.57 | 0.02 | ||
| Stanislaus | Central Valley | 2.99 | 0.04 | ||
| 1978–1982 | Hispanic | San Luis Obispo | Southern California | 5.83 | 0.008 | 
| Santa Barbara | Southern California | 3.31 | 0.03 | ||
| Fresno | Central Valley | 2.99 | 0.04 | ||
| Kern | Southern California | 2.99 | 0.04 | ||
| 1983–1987 | Non-Hispanic | Sacramento | Central Valley | 2.99 | 0.04 | 
| Santa Cruz | San Francisco Bay | 2.99 | 0.04 | ||
| 1988–1992 | Hispanic | Alameda | San Francisco Bay | 15.42 | <0.001 | 
| Ventura | Southern California | 11.95 | <0.001 | ||
| Non-Hispanic | Los Angeles | Southern California | 4.57 | 0.02 | |
| San Bernardino | Southern California | 2.99 | 0.04 | 
aSouthern California = Imperial, Kern, Los Angeles, Orange, Riverside, San Bernardino, San Diego, San Luis Obispo, Santa Barbara, and Ventura Counties; Central Valley = Colusa, Fresno, Glenn, Kings, Madera, Merced, Sacramento, San Joaquin, Solano, Stanislaus, Sutter, Tulare, and Yolo Counties; San Francisco Bay = Alameda, Contra Costa, Marin, San Francisco, San Mateo, Santa Clara, and Santa Cruz Counties.
bp-value based on one-sided chi-square test with 1 degree of freedom.
1 Preliminary results of this study were presented at the 9th Symposium of the International Society for Veterinary Epidemiology and Economics, August 6–11, 2000, Breckenridge, Colorado, USA.