Effects of practice and learner control on short- and long-term gain and efficiency.

This study investigated the effects of practice opportunities and learner control on short- and long-term learning from a computer-based introductory statistics curriculum. In all, 380 participants were assigned to one of five conditions. The first four conditions differed in terms of the number of problems to solve per problem set. The fifth condition allowed learners to choose the amount of practice. A subset (n = 120) of the original participants returned for testing following a six-month interval. Overall, the fixed-practice conditions showed learning gains that varied in relation to the amount of practice (i.e., more was better). The data from the learner-control condition was unexpected, showing learning gains comparable with the most extended practice condition yet the fastest tutor-completion times. We discuss implications of these findings in relation to the design of efficacious instruction. Actual or potential applications of this research include the modification of computer-based instruction that can enhance individuals' learning efficiency and outcome scores.

A preliminary report of Norplant implant insertions in a large urban family planning program.

During the 21-month period between August 1, 1991, and April 30, 1993, 2,358 women received Norplant system insertions in either Parkland Memorial Hospital or the Dallas Maternal Health and Family Planning clinics. Forty-three percent of these women were teenagers with 14% 16 years of age or less. Overall, 431 patients received Norplant implants insertions postpartum prior to discharge from the hospital. To date, 138 Norplant systems have been removed, with the proportion of contraceptive implant removals among teenagers being essentially the same as that in more mature women. Of the reasons given by women discontinuing the Norplant system, an unanticipated high incidence of pain in the arm containing the implants, hair loss, and mood changes were noted. We have found the Norplant system to be a highly effective and highly acceptable contraceptive method for a large number of indigent women.

PIP: Between August 1991 and April 1993, in Texas, family planning specialists analyzed prospective data on 2358 women who underwent Norplant system insertions at either the Division of Maternal Health and Family Planning clinics of the University of Texas Southwestern Medical Center or at Parkland Memorial Hospital. The household income of about 90% of the women was at or below the poverty level. Health workers counseled each woman expressing interest in Norplant individually so the women understood the risks, benefits, and side effects. The women had access to health workers via telephone, clinic appointment, or clinic walk-in visits when they had questions and concerns. At the time of insertion, 43% of the women were no older than 19 years of age. 14% were 16-years-old or younger. 63% of the 431 women who received Norplant immediately after delivery were no more than 19-years-old. 74% of all the women had at least one concern about Norplant. The leading concern was pain at the time of insertion (32.1%) followed by weight changes (14.8%), and menstrual changes (12.2%). As of August 1993, only 138 (5.85%) of the women requested removal (adolescents = 40%). The reasons for removal included irregular bleeding (41.3%), headache (22.5%), pain in the arm with Norplant (18.1%), weight gain (14.5%), hair loss (10.1%), mood changes (8%), and desire for pregnancy (8%). The researchers had not anticipated the high incidence rates of arm pain, hair loss, and mood changes. These findings suggested that Norplant is an acceptable longterm contraceptive method. Other studies showed that it is also very effective.

HIV prevalence in pregnant intravenous drug users in Dallas, Texas.

Information available regarding the prevalence of human immunodeficiency virus (HIV) in pregnant women indicates that the primary risk factor for infection is intravenous drug use. At Parkland Memorial Hospital in Dallas, Texas, approximately 4.7% of pregnant women reported using intravenous drugs. The estimated prevalence of HIV infection among pregnant intravenous drug users at this hospital was 3.3%. This is similar to the HIV infection rates reported for nonpregnant parenteral drug-using populations in other areas of the southwestern United States, suggesting that there may be a lower rate of endemic infection in this region of the country.

An immunogold assay system for the detection of antigen or antibody.

A colloidal gold-based semi-quantitative manual immunoassay method for the detection of antibody or antigen has been developed. The colloidal gold particles are coated with an organic reagent which, in turn, is attached to the antibody by covalent bonds. The antibody or the antigen are immobilized on simple chromatography paper. The paper strips are developed with an appropriate immunogold reagent in a test tube in the presence of urine (Pregnancy or Ovulation test) or serum (Rubella test). The mixture migrates up the strips towards the test band. A purple band develops which indicates the presence of the corresponding antigen (Pregnancy, Ovulation test) or antibody (Rubella test). In this format, 50 mIU or more of hCG in urine can be detected in 5 minutes or less, and antibody to Rubella virus at an HAI titer equivalent of 8 or above in serum can be detected in 10 minutes or less. These test kits, known as Result Plus test systems, are simple, rapid, highly sensitive, and require no instruments to perform.