Illusory correlation: a function of availability or representativeness heuristics?

The present study sought to investigate the illusory correlation phenomenon by experimentally manipulating the availability of information through the use of the "lag" effect (Madigan, 1969). Seventy-four university students voluntarily participated in this study. Similar to Starr and Katkin's (1969) methodology, subjects were visually presented with each possible combination of four experimental problem descriptions and four sentence completions that were paired and shown twice at each of four lags (i.e., with 0, 2, 8 and 20 intervening variables). Subjects were required to make judgements concerning the frequency with which sentence completions and problem descriptions co-occurred. In agreement with previous research (Starr & Katkin, 1969), the illusory correlation effect was found for specific descriptions and sentence completions. Results also yielded a significant effect of lag for mean ratings between 0 and 2 lags; however, there was no reliable increase in judged co-occurrence at lags 8 and 20. Evidence failed to support the hypothesis that greater availability, through the experimental manipulation of lag, would result in increased frequency of co-occurrence judgements. Findings indicate that, in the present study, the illusory correlation effect is probably due to a situational bias based on the representativeness heuristic.

Suicide-intervention trainees' perceptions of awareness for warning signs of suicide.

55 trainees in suicide intervention were administered a revised version of the Suicide Opinion Questionnaire to examine the effects of suicide intervention training and experience in suicide prevention on their perceptions about the availability of suicide warning signs. Over-all, results indicated that most participants agreed with the ideas that warning signs of suicide are usually evident and that family members of those who have committed suicide may not be aware of these signs. Effects of intervention training on perceptions about the availability of suicide warning signs were not evident. Multivariate analysis indicated that participants with less than one year of experience in suicide prevention expressed significantly (p < .01) more agreement than participants with between one and five years of experience in suicide prevention for the idea that family members may not be aware of suicide warning signs in their suicidal relatives.

Combination of ABO blood group incompatibility and glucose-6-phosphate dehydrogenase deficiency: effect on hemolysis and neonatal hyperbilirubinemia.

The incidence (%) of hyperbilirubinemia (serum bilirubin > or = 257 micromol/l) was similar in neonates with a combination of ABO incompatibility and glucose-6-phosphate dehydrogenase (G-6-PD) deficiency (45%), with ABO incompatibility (54%) or G-6-PD deficiency (37%), alone (ns). Carboxyhemoglobin values, corrected for inspired CO, were similarly elevated in all three groups (0.87 +/- 0.32%, 0.82 +/- 0.29%, 0.76 +/- 0.18%, respectively, ns), but correlated with bilirubin only in those with ABO incompatibility alone. ABO-incompatible/G-6-PD-deficient neonates, compared with those with either condition alone, are not at increased risk for hemolysis or hyperbilirubinemia.

Intravenous access in newborn infants: impact of extended umbilical venous catheter use on requirement for peripheral venous lines.

Central venous lines are used to care for critically ill neonates in cases of limited peripheral venous access. This prospective, randomized study evaluated the risks and benefits of the use of single- and double-lumen umbilical venous catheters for up to 14 days. Patients were randomized to one of three treatment arms: (1) single-lumen umbilical catheter, (2) double-lumen umbilical catheter, or (3) no umbilical catheter; peripheral intravenous lines only. Infants in the groups treated with an umbilical venous catheter had significantly fewer venipunctures and peripheral intravenous lines placed during their first 2 weeks of life than those in the peripheral line only group. Less time and money were spent obtaining peripheral line placement in the umbilical venous catheter groups. The incidence rates of sepsis and complications were not higher in treated patients than in control patients. The double-lumen catheter further reduced peripheral venipunctures and lines. We conclude that an umbilical venous catheter used during the first 2 weeks of life is a relatively safe, less stressful, cost-effective means of providing intravenous therapy to neonates.

Persistent pulmonary hypertension in newborn infants with cogenital myotonic dystrophy.

We describe two infants with congenital myotonic dystrophy that was complicated by persistent pulmonary hypertension. Both infants died of respiratory insufficiency that was unresponsive to ventilatory and pharmacologic support. One of the two infants was supported with extracorporeal membrane oxygenation before the diagnosis of congenital myotonic dystrophy was made.

Cerebrospinal fluid and plasma beta-endorphin-like immunoreactivity in full-term neonates and in preterm neonates with and without apnea of prematurity.

Beta-endorphin-like immunoreactivity (B-ELI) was measured in cerebrospinal fluid (CSF) and plasma from infants of postnatal age 24 h to 70 days. Three groups were examined: 17 were of postconceptual age greater than or equal to 37 weeks, 16 were postconceptual age less than or equal to 35 weeks without apnea and 10 were of postconceptual age less than or equal to 35 weeks with apnea. All infants were clinically stable. Two-way analysis of variance between groups showed no difference in the concentration of B-ELI in CSF or plasma, or in the CSF/plasma B-ELI ratio. Concentrations of B-ELI in plasma were significantly higher in infants of postnatal age 1-3 weeks and greater than or equal to 4 weeks, than in infants of postnatal age less than 1 week. We conclude that, in nonstressed infants, there is no relationship between the concentration of B-ELI in CSF or plasma and a concurrent diagnosis of apnea of prematurity. Our data indicate that a significant developmental increase occurs in the plasma concentration of B-ELI after the first week of life.

Low incidence of acquired cytomegalovirus infection in neonates transfused with washed red blood cells.

To define the incidence of cytomegalovirus (CMV) infection in infants given transfusions of washed blood cells from random donors, 100 infants who were identified as being CMV seronegative at birth were resampled at hospital discharge and again six weeks after hospitalization. All infants received washed red blood cell products; 37 infants received nonleukodepleted platelets and/or plasma. There were 7.4 donor exposures per infant. Donor units were assayed for anti-CMV IgG and IgM at the time of donation. Seventy-six infants received at least one transfusion from a seropositive donor (mean transfusion volume, 89 mL; mean, 3.7 seropositive donor exposures). Infection was defined by seroconversion to anti-CMV. None of the recipients of exclusively seronegative blood seroconverted. A single infant who received 34 mL of washed cells from a seropositive donor (IgG+, IgM-) and 31 mL of washed cells from a seronegative donor showed IgM anti-CMV 15 days after transfusion and IgG anti-CMV at a six-week follow-up visit. No recipients of IgM+ blood were infected. Our data demonstrate a 1.3% incidence of anti-CMV seroconversion following receipt of washed red cells from seropositive donors. This rate is within background levels for hospitalized neonates and is significantly lower than results of similar studies using unwashed blood.

The potential toxicity to neonates of multivitamin preparations used in parenteral nutrition.

This study compares two groups of infants weighing less than 1500 g at birth. In the propylene glycol (PG) group, 30 infants received MVI-Concentrate containing 300 mg of PG daily with their intravenous nutrition (ivn), and vitamin E, 50 mg/week by intramuscular injection. In the mannitol group, 30 infants received MVI-Pediatric (containing 245 mg mannitol), 65% of a vial/day. Serum and urine osmolality, serum PG, blood-urea-nitrogen, creatinine, sodium, and glucose were measured on days 0, 2, 5, 12, 19, 26, 33 and 40 of ivn. Weight, urine output, and fluid intake were measured daily. Vitamin E levels were measured on days 5, 26, and 33 of ivn. There were no significant differences between the groups in birth weight, gestational age, sex, age, or weight at start of ivn. Our results indicated that neither MVI-Concentrate nor MVI-Pediatric was associated with a clinically significant diuresis. MVI-Pediatric, 65% of a vial/day, may produce higher than desirable blood levels of vitamin E, and use of drugs containing PG can produce significant blood levels of PG, in very low birth weight infants.

AIDS, HTLV-III diseases, minorities and intravenous drug abuse.

Minorities and women who are engaging in activities which place them at high risk for infection with HTLV-III are developing HTLV-III related illnesses including AIDS. In Northeastern urban areas the relatively large number of minorities who use intravenous drugs are responsible for producing large numbers of patients with AIDS (PWAs). Eighty percent of heterosexual male and female PWAs are Black or Hispanic. The development and implementation of effective prevention and education programs for these individuals rests upon an understanding of the less traditional approaches which may be necessary to reach these groups. The general public must be made aware of the hazards of HTLV-III related diseases and that the risk of infection is restricted to very well defined high risk groups. Minorities must be made to understand that they are at increased risk for HTLV-III related diseases only because of the high incidence of drug abuse in their community.

Preventing complications from lines and tubes.

Rather than providing an exhaustive list of known complications of all tubes and lines used in the NICU, we have highlighted the potentially traumatic nature of their use and outlined general principles of prevention. Most complications of care are more easily avoided if we know about them in advance. Attention to simple details, while recognizing that use of indwelling tubes and lines has both benefits and hazards, should lessen some of these morbidities.

Effect of naltrexone on apnea of prematurity and on plasma beta-endorphin-like immunoreactivity.

Plasma levels of beta-endorphin-like immunoreactivity (beta-ELI) were measured in premature infants with apnea (n = 11) and compared to those in nonapneic controls (n = 9). Naltrexone (1-3 mg/kg) was given to the infants with apnea, 6 of whom were also receiving methylxanthines. Chest wall movements, nasal airflow, transcutaneous PO2 and electrocardiogram were recorded for 4-6 h prior to and for 4-6 h after administration of naltrexone. Samples for beta-ELI were taken prior to and 1 h post naltrexone. beta-ELI levels were significantly higher (p less than 0.007) in infants with apnea of prematurity than in control infants. No significant difference was found in beta-ELI levels before and after naltrexone. Naltrexone did not decrease the incidence of apnea.

Health education and knowledge assessment of HTLV-III diseases among intravenous drug users.

PIP: The human T-cell lymphotropic virus, type III (HTLV-III) is the causative agent of acquired immunodeficiency syndrome (AIDS). Since AIDS is not curable, public health efforts must be focused on decreasing AIDS transmission. 72% of all AIDS cases are male homosexuals; 17% are intravenous (IV) drug users; and 3% are hemophiliacs, blood recipients, and infants of these groups. The gay community is sufficiently organized to provide the necessary infrastructure for AIDS education and treatment; the drug users are not, and at least 1/3 of IV drug users share needles and syringes. In 1984 a cooperative study was undertaken in New Jersey by the New Jersey State Department of Health, the National Cancer Institute (NCI), and the National Institute on Drug Abuse (NIDA) to determine the seroprevalence of HTLV-III among IV drug users and to assess their knowledge about AIDS. Over 95% knew the severer symptoms of AIDS; 76% knew that most AIDS patients die within 2 years of diagnosis; but 9% thought AIDS could be treated. A year later in 1985 a similar knowledge assessment survey was done among 577 clients entering drug treatment programs in New Jersey. 90% of these respondents knew that homosexuals and IV drug users were the primary risk groups, but 11% thought alcoholics were also at risk, and 43% did not know that the infants of drug users were at risk. 84% knew that sex and shared needles were the major modes of transmission, but 1/3 thought that an infected person would immediately show visible signs of illness, and many did not know how rapidly AIDS killed. Also, many did not know how to adequately clean syringes. They thought boiling would damage the syringes, and only 1/3 knew that a dilute solution of household bleach kills the virus. New Jersey decided to use indigenous health workers, recruited from rehabilitated drug users, to educate the drug community. The core message was: get treatment; don't share needles; and if you must share needles, clean them. The same message reaches drug users on late-night television and radio and English language newspapers. Drug users are educable; whether education and peer pressure will effect behavior modification remains to be seen.^ieng