Statistics: concepts, methods, and applications

¶ … graphs were complied from the results of the demographic breakdown of people who tested for HIV in a study conducted in 8 counties and across 27 zip codes. The test was conducted over a period of approximately 2 1/2 years.

Counselors, who conducted the tests, were able to contact and test a total of 270 people. The test subjects were screened and coded for behavioral or other risk factors, such as hemophilia, blood recipient, intravenous drug users, etc. The subjects were further broken down by race, age and gender.

The subjects were further broken down by how many additional times they visited the testing centers and follow up visits. In all 242 people chose to visit the test centers 1 additional time, while 22 returned twice and 1 subject returned 3 times. Of the subjects who tested positive for HIV, none returned to the center more then once. Fourteen of the 22 HIV test subjects met with a follow-up counselor.

Of all those studied 119 had a single risk factor, a majority of those being Heterosexual risk factors. 123 had multiple risk factors. Considering the high number of multiple risk factors it is interesting to not the relatively low occurrence of HIV in the study group. Although among 18% of the group that did test positive for HIV had multiple risk factor behavioral scores.

The results from the tests show that among Hispanics who tested positive from the tested group 100% were male, while among the blacks that tested positive from the tested group, 100% were female. Of the 22 test subjects who tested positive for HIV, 14 had no known HIV risk factors prior to testing, while four had a single risk factor and 4 had multiple risk factors.

Below is a chart defining the codes for risk factors. The results from the test subjects showed that the majority of those who tested HIV positive had no known risk factors prior to testing. Of those that did have risk factors, the breakdown was roughly half with multiple risk factors and half with a single risk factor.

The following is an explanation of the Risk factors codes:

Code

Value

Men who had sex with men

Intravenous drug users (IDU)

Hemophilia

Blood recipient

Heterosexual

Sex Partner (SP) of Homosexual/bisexual (for females)

SP=IDU (Intravenous Drug Use)

SP-Person with AIDS (PWA)/HIV+

SP of hemophiliac

Exchange drugs/money for sex

SP of Blood recipient

SP of prostitute

Sex while using noninjection drugs

Occupational exposure

Parent with HIV / AIDS

Tattoo/Acupuncture/Steroids

NO known risk

Rape/sexual assaulted victim

Sexually Transmitted Disease (STD) diagnosis

Racial makeup was coded as follows:

Ethnicity code values

Code

Value

White

Hispanic

Black

American Indian/Alaskan Native

The charts below is a break down of the results conducted on 270 people for HIV:

Total Tested

Negative

Positive

No results

Below is the graphical breakdown by percentage of those who tested positive for HIV. As can be seen by the chart less then 10% of the total tested actually returned a positive result.

The test results as noted on the following chart show that those who tested positive for HIV overwhelming had no know risk factors, as graded by the counselors who met with the subjects and conducted the tests. The subjects were tested and given the opportunity to return for a second or more times. Most subjects did return once.

Risk factors broken down by code and total number of HIV positive test results per risk factor:

The chart clearly illustrates that the highest number of positive test results for the Aids virus were those who were coded Q, which is no known risk factors prior to testing.

While 14 cases tested positive for the HIV virus that had no known risk factors, there was 1 case each for each of the other factors noted and 4 instances where the subject had multiple risk factors assigned. As mentioned earlier of the 22 who tested positive for HIV all chose to return once for a second visit, and 15 met with a counselor.