Measurement of delusional ideation in the normal population: introducing the PDI (Peters et al. Delusions Inventory). (1/24)

The Peters et al. Delusions Inventory (PDI) was designed to measure delusional ideation in the normal population, using the Present State Examination as a template. The multidimensionality of delusions was incorporated by assessing measures of distress, preoccupation, and conviction. Individual items were endorsed by one in four adults on average. No sex differences were found, and an inverse relationship with age was obtained. Good internal consistency was found, and its concurrent validity was confirmed by the percentages of common variance with three scales measuring schizotypy, magical ideation, and delusions. PDI scores up to 1 year later remained consistent, establishing its test-retest reliability. Psychotic inpatients had significantly higher scores, establishing its criterion validity. The ranges of scores between the normal and deluded groups overlapped considerably, consistent with the continuity view of psychosis. The two samples were differentiated by their ratings on the distress, preoccupation, and conviction scales, confirming the necessity for a multidimensional analysis of delusional thinking. Possible avenues of research using this scale and its clinical utility are highlighted.  (+info)

The Hound of the Baskervilles effect: natural experiment on the influence of psychological stress on timing of death. (2/24)

OBJECTIVE: To determine whether cardiac mortality is abnormally high on days considered unlucky: Chinese and Japanese people consider the number 4 unlucky, white Americans do not. DESIGN: Examination of cardiac and non-cardiac mortality on and around the fourth of each month in Chinese and Japanese subjects and white controls. SETTING: United States. SUBJECTS: All Chinese and Japanese (n=209 908) and white (n=47 328 762) Americans whose computerised death certificates were recorded between the beginning of January 1973 and the end of December 1998. MAIN OUTCOME MEASURES: Ratio of observed to expected numbers of deaths on the fourth day of the month (expected number was estimated from mortality on other days of the month). RESULTS: Cardiac mortality in Chinese and Japanese people peaked on the fourth of the month. The peak was particularly large for deaths from chronic heart disease (ratio of observed to expected deaths = 1.13, 95% confidence interval 1.06 to 1.21) and still larger for deaths from chronic heart disease in California (1.27, 1.15 to 1.39). Within this group, inpatients showed a particularly large peak on the fourth day(1.45, 1.19 to 1.81). The peak was not followed by a compensatory drop in number of deaths. White controls, matched on age, sex, marital status, hospital status, location, and cause of death, showed no similar peak in cardiac mortality. CONCLUSIONS: Our findings of excess cardiac mortality on "unlucky" days are consistent with the hypothesis that cardiac mortality increases on psychologically stressful occasions. The results are inconsistent with nine other possible explanations for the findings-for example, the fourth day peak does not seem to occur because of changes in the patient's diet, alcohol intake, exercise, or drug regimens.  (+info)

The mummy's curse: historical cohort study. (3/24)

OBJECTIVE: To examine survival of individuals exposed to the "mummy's curse" reputedly associated with the opening of the tomb of Tutankhamen in Luxor, Egypt, between February 1923 and November 1926. DESIGN: Retrospective cohort study. PARTICIPANTS: 44 Westerners identified by Howard Carter as present in Egypt at the specified dates, 25 of whom were potentially exposed to the curse. MAIN OUTCOME MEASURES: Length of survival after date of potential exposure. RESULTS: In the 25 people exposed to the curse the mean age at death was 70 years (SD 12) compared with 75 (13) in those not exposed (P=0.87 for difference). Survival after the date of exposure was 20.8 (15.2) v 28.9 (13.6) years respectively (P=0.95 for difference). Female sex was a predictor for survival (P=0.02). CONCLUSIONS: There was no significant association between exposure to the mummy's curse and survival and thus no evidence to support the existence of a mummy's curse.  (+info)

Experimental control of superstitious responding inhumans. (4/24)

Superstitions were demonstrated with human subjects when presses on one button were reinforced on a VI 30-sec schedule while presses on a second were never reinforced. Superstitious responding, on the second button, was often maintained because presses on that button were frequently followed by reinforcement for a subsequent press on the first button. The introduction of a changeover delay (COD), which separated in time presses on the second button and subsequent reinforced presses on the first button, reduced or eliminated the superstitious responding of these subjects. Some complex superstitions were also demonstrated with other subjects for which the COD was in effect from the beginning of the session.  (+info)


The reaction to modern medicine and the general health of the new immigrants and Arab populations of Israel are described. The material was gathered during a threemonth visit to Israel where the author participated in the medical care of these persons. While these peoples still share many of the traditional medical superstitions and practices, the new immigrants have progressed much more during the 16 years of Israel's existence. At present over 99% of Jewish women give birth in hospital, whereas only 65% of Israeli Arabs do. The infant mortality rate among the Jews in 1963 was about 21 deaths per 1000 live births, about one-half the rate for Arabs. The importance of understanding the cultural background and social conflicts of these people as a preliminary to the provision of proper medical care is stressed.  (+info)

Females do not have more injury road accidents on Friday the 13th. (6/24)

BACKGROUND: This study reinvestigated the recent finding that females - but not males - die in traffic accidents on Friday the 13th more often than on other Fridays (Nayha S: Traffic deaths and superstition on Friday the 13th. Am J Psychiatry 2002, 159: 2110-2111). The current study used matched setting and injury accident data base that is more numerous than fatality data. If such an effect would be caused by impaired psychic and psychomotor functioning due to more frequent anxiety among women, it should also appear in injury crashes. METHODS: We used the national Finnish road accident database for 1989-2002. To control seasonal variation, 21 Fridays the 13th were compared in a matched design to previous and following Fridays, excluding all holidays, on number of accidents, male/female responsibility for accidents, and the number of dead, injured and overall number of active participants (drivers, pedestrians and bicyclists) as a consequence of the accident. RESULTS: There were no significant differences in any examined aspect of road injury accidents among the three Fridays, either in females or males. Women were not overrepresented in crashes that occurred on Fridays 13th. CONCLUSION: There is no consistent evidence for females having more road traffic crashes on Fridays the 13th, based on deaths or road accident statistics. However, this does not imply a non-existent effect of superstition related anxiety on accident risk as no exposure-to-risk data are available. People who are anxious of "Black Friday" may stay home, or at least avoid driving a car.  (+info)

Prevalence of epilepsy its treatment gap and knowledge, attitude and practice of its population in sub-urban Senegal an ILAE/IBE/WHO study. (7/24)

A door-to-door survey was used to determine the prevalence of epilepsy among 4500 people within the Pikine Health District (population 480,000) Senegal. Prevalence was 14.2/1000, and 23.4% of all people with epilepsy had never received appropriate treatment. Figures for the prevalence had increased since a previous survey in 1989. In parallel a study of knowledge attitude and practice was performed in the same district. Salient findings were that: two-thirds of interviewees had at some time witnessed a seizure, 51% agreed when asked if epilepsy is caused by evil spirits, 35% said epilepsy is contagious, only about 18% said that traditional therapy is best, 60% would not mind their child to play with a child with epilepsy but only 32% would agree if their child would want to marry a person with epilepsy.  (+info)

Experience of isolated sleep paralysis in clinical practice in Nigeria. (8/24)

The supernatural fears associated with the experience of isolated sleep paralysis in the culture of developing countries is sometimes associated with the evolution of somatic symptoms of psychological origin in patients predisposed to neurotic illness. Patients rarely spontaneously volunteer these fears and doctors pay them scant attention. Illustrative case histories that demonstrate the dynamics of the clinical presentation, as well as the treatment approach, are highlighted. It is hoped that doctors in general medical practice and in psychological medicine in developing countries where belief in supernatural causation of illness is rife will consider these factors in order to provide more effective treatment.  (+info)