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Biomedical subjects

S M Banks

Publications and source records attributed to S M Banks.

At least 73 records · Page 4Linked to original sources
PubMed1994

Acrosome reaction inducibility predicts fertilization success at in-vitro fertilization.

We prospectively studied the ability of acrosome reaction (AR) inducibility to predict fertilization success in a group of 232 infertile patients presenting sequentially for in-vitro fertilization (IVF). The median percentage of eggs fertilized for the overall patient population was 25% (interquartile range 5-58%), with one to 29 oocytes available for insemination (median, five oocytes). The median percentage of eggs fertilized at IVF increased as the percentage of spermatozoa able to undergo AR became greater: spermatozoa with a failed AR (< or = 5%) fertilized only 12% of eggs, while spermatozoa with AR values > 9% fertilized 50% of eggs. The assay had a specificity of 0.75, a sensitivity of 0.55 and an odds ratio of 2.9; thus, AR-positive patients are 2.9 times more likely to achieve fertilization than patients with a failed AR. Receiver operator characteristic (ROC) curves were constructed for AR, sperm concentration and percentage of normal forms in semen. All three parameters proved to be potentially useful in predicting the occurrence of fertilization, although AR and morphology appeared to be better than sperm concentration by ROC analysis. Patients were divided into four clearly defined subgroups according to their traditional semen characteristics, including morphology. The median percentage of eggs fertilized decreased as traditional semen characteristics deteriorated, from a median of 46% for patients with excellent sperm concentration, motility and morphology, to a median of 29% for patients with suboptimal semen quality and a median of 0% for patients with severely impaired semen.(ABSTRACT TRUNCATED AT 250 WORDS)

Acrosome↗
PubMed1994

Cardiopulmonary effects of granulocyte colony-stimulating factor in a canine model of bacterial sepsis.

We investigated the effects of recombinant granulocyte colony-stimulating factor (G-CSF) in a canine model of septic shock. Awake 2-yr-old beagles were studied before and after intraperitoneal placement of an Escherichia coli-infected clot. Nine days before and until 3 days after clot placement, animals received daily high-dose (G-CSF (5 microgram/kg body wt; n = 17), low-dose G-CSF (0.1 microgram/kg body wt; n = 17), or a control protein (5 micrograms/kg body wt; n = 20). Survival rate was greater (P < 0.04, Wilcoxon test) in the high-dose G-CSF group (14/17) than in the low-dose G-CSF (10/17) and control (12/20) groups. High-dose G-CSF improved cardiovascular function, as evidenced by increased left ventricular ejection fraction (day 1 after clot; P < 0.001) and mean arterial pressure (day 2; P < 0.02) compared with low-dose G-CSF and control groups. High-dose G-CSF increased (P < 0.001) mean peripheral neutrophils before (-3 days) and after (2 h to 4 days) clot and produced a more rapid (P < 0.001) rise (day 2) and fall (day 4) in mean alveolar neutrophil numbers compared with the low-dose G-CSF and control groups. High-dose G-CSF decreased mean serum endotoxin (2-8 h; P < 0.002) and tumor necrosis factor (2 h; P < 0.02) levels and lowered blood bacteria counts (2-6 h; P < 0.04) compared with the low-dose G-CSF and control groups. Thus, in this canine model, G-CSF sufficient to increase peripheral neutrophils before and during peritonitis and septic shock enhances host defense, reduces cytokine (tumor necrosis factor) levels, and improves cardiovascular function and survival.

Animals↗
PubMed1993

A controlled trial of HA-1A in a canine model of gram-negative septic shock.

OBJECTIVE: To investigate the therapeutic efficacy and microbiological and physiological effects of a human IgM monoclonal antibody (HA-1A) directed against the lipid A component of endotoxin in a canine model of sepsis that simulates the cardiovascular abnormalities of human septic shock. DESIGN: Blinded, placebo-controlled 28-day trial. INTERVENTIONS: Purpose-bred beagles were implanted with an intraperitoneal clot infected with Escherichia coli O111:B4. At clot placement, animals received HA-1A (10 mg.kg-1), control human IgM antibody (10 mg.kg-1), or control human serum albumin intravenously. All animals were given antibiotic and fluid therapy. MEASURES: Survival and microbiological and physiological events. RESULTS: Only two (15%) of 13 animals in the HA-1A group, compared with eight (57%) of 14 control animals (combined control human IgM antibody and control human serum albumin groups) (P = .05), survived 28 days. At 24 hours, the HA-1A group had lower mean arterial pressure (P = .04) and cardiac index (P = .004) and higher lactate levels (P = .05) compared with the combined-controls group. In addition, these parameters in the HA-1A group were significantly more predictive of death. The HA-1A and combined-controls groups had similar significant increases in the level of endotoxemia and bacteremia. Studies of toxic effects showed no harmful effects of control human IgM antibody in infected animals or HA-1A in non-infected animals. CONCLUSION: In a canine model of E coli sepsis, HA-1A did not alter levels of bacteremia or endotoxemia and actually decreased survival. If these data are relevant to human septic shock, HA-1A therapy should be limited until the conditions under which this monoclonal antibody has beneficial or deleterious effects are more completely defined.

Animals↗
PubMed1993

Clinical and serological differentiation of autoimmune and hepatitis C virus-related chronic hepatitis.

Recent reports have focused on the difficulty in differentiating autoimmune hepatitis from chronic hepatitis C due to the high prevalence of anti-HCV in autoimmune hepatitis. The aim of this study was to identify clinical, biochemical, and serological variables that would help distinguish these two diseases. Pretreatment clinical and biochemical variables were compared from 17 patients with steroid-responsive autoimmune chronic active hepatitis and 62 patients with chronic hepatitis C. Serum samples from these patients were tested for autoantibodies and for anti-HCV by first- and second-generation ELISA, recombinant immunoblot assay, and HCV RNA by polymerase chain reaction. Patients with autoimmune hepatitis were more likely to be symptomatic (94% vs 47%, P < 0.005) and jaundiced (76% vs 0%, P < 0.005) at the time of referral. Anti-HCV was found in 53% of patients with autoimmune hepatitis, but only two were positive by immunoblot assay and only one of these had detectable HCV RNA. Antinuclear antibody (ANA) was detected in 21% of patients with chronic hepatitis C, although usually at a lower titer than in autoimmune hepatitis (geometric mean titer = 1:160 vs 1:500, P < 0.003). Patients with chronic hepatitis C who were ANA positive were older than those who were ANA negative, although there were no other differences in clinical or biochemical features between these groups. In particular, there was no difference in response rate to antiviral therapy. Thus, autoantibodies are frequently found in chronic hepatitis C, especially in older subjects, but appear to be clinically insignificant. Anti-HCV is frequently present in autoimmune hepatitis but is rarely confirmed by tests of higher specificity.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

The effects of interleukin-1 therapy on peripheral blood granulocyte function in humans.

During a phase I trial of interleukin-1 alpha (IL-1 alpha) in patients with ovarian carcinomas, the effects of this treatment on blood granulocyte respiratory burst and locomotive responses were examined. Differences in baseline granulocyte function in patients as well as dose-related effects of IL-1 alpha treatment were observed. Patients enrolled early in the trial (low-dose patients) had significantly lower locomotive responses before treatment than their paired controls; these low responses normalized after 5 days of continuous-infusion IL-1 alpha treatment. Patients enrolled later (high-dose patients) had normal locomotive responses before treatment and IL-1 alpha treatment was associated with suppression of responses to selected stimuli at the end of treatment. Pretreatment respiratory burst responses in both low- and high-dose patient groups were essentially normal, but the rates of granulocyte H2O2 production following phorbol myristate acetate stimulation became significantly less than control values at the end of treatment. In vitro exposure of either patient or control cells to 150 U/ml IL-1 alpha did not alter their locomotive or respiratory burst responses, suggesting the observed in vivo effects were not mediated directly by IL-1 alpha. Treatment with IL-1 alpha is associated with changes in ex vivo granulocyte function that are related to the IL-1 alpha dose. Treatment with low doses of IL-1 alpha may provide a means of normalizing abnormal polymorphonuclear leukocyte function in some patients with ovarian malignancies.

Analysis of Variance↗
PubMed1993

Plasma exchange does not improve survival in a canine model of human septic shock.

Whether plasma exchange would improve survival in antibiotic-treated canines with septic shock was investigated. Escherichia coli O86H8 (1.4 X 10(10)) was surgically implanted as an intraperitoneal clot in 18 two-year-old (10-12 kg) purpose-bred beagles. Beginning 4 hours after surgery, all animals received cefoxitin and gentamicin for 5 days. Three treatment groups were defined: 1) a no apheresis, or control group, (n = 6); 2) a sham apheresis group, whose whole blood plasma was removed, separated, and then transfused (n = 6); and 3) a plasma exchange group from whom blood and plasma were removed and separated, to whom the blood was returned, and in whom infected plasma was replaced with compatible fresh-frozen canine plasma (n = 6). For the sham apheresis and plasma exchange groups, a commercial blood cell processor was used to separate 1.5 blood volumes of plasma at 5 and 24 hours after surgery. Serial radionuclide left ventricular ejection fractions and femoral and pulmonary arterial catheter hemodynamics were measured simultaneously in awake animals. All six animals in the plasma exchange group died. In both the sham and control groups, only one of six animals survived. Survival times were ordered (median in hours) (control [372 h] > sham apheresis [48 h] > plasma exchange [24 h] [p < 0.038]). Decreases in mean cardiac index and mean arterial pressure (from before apheresis to after) at 5 to 7 hours after surgery were ordered (plasma exchange > sham apheresis > control; p < 0.03). Thus, plasma exchange in this controlled trial of septic shock was associated with decreased survival and worsened hemodynamics.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1993

Thyroid hormone levels affected by time of blood sampling in thyroxine-treated patients.

Patients receiving exogenous levothyroxine are reported to have higher total and free serum thyroxine levels than euthyroid controls. This may be an artifact of the serum collection time. We explored the effect of collection time on serum levels of thyroid hormones in outpatients receiving levothyroxine for replacement therapy (26 patients) or suppression of thyrotropin (25 patients). Blood samples, obtained during regular clinic visits (random samples) and at more than 22 h from ingestion of levothyroxine (trough samples), were assayed for total and free thyroxine, triiodothyronine, and thyrotropin. Four athyreotic patients on levothyroxine therapy had serial blood sampling over 24 h. Compared to corresponding trough samples, random samples had elevated total thyroxine levels in patients receiving replacement (8.1 +/- 1.2%, mean +/- SE, p = 0.0001) and in patients undergoing suppression (8.8 +/- 1.6%, p = 0.0001). Free thyroxine was increased by 12.7 +/- 2.6% (p = 0.0003) and 14.5 +/- 2.3% (p = 0.0001), respectively, compared with trough samples. Thyrotropin levels were 18.9 +/- 6.8% (p = 0.003) lower in patients receiving replacement and triiodothyronine levels showed small or no changes. Time-course analysis showed that free and total thyroxine levels remained significantly elevated above baseline for 9 and 5 h, respectively, after a levothyroxine dose. In conclusion, there is a transient increase in thyroid hormone levels for 9 h after an oral levothyroxine dose. Accurate assessment of thyroid hormone levels in patients receiving levothyroxine therapy should take this into account. This has greatest significance in selecting minimal levothyroxine dosages for suppression of thyrotropin.

Administration, Oral↗
PubMed1993

Chemical composition and protein source in the capacitation medium significantly affect the ability of human spermatozoa to undergo follicular fluid induced acrosome reaction.

We studied the effect of media composition on sperm capacitation, using Biggers-Whitten-Whittingham (BWW) medium, Ham's-F10 and a modified Tyrode's medium (HSM) supplemented with bovine serum albumin (BSA) or fetal cord serum (FCS). We evaluated the effect of chemical environment and protein supplementation on the sperm motion parameters of curvilinear velocity and linearity, and on the ability of incubated spermatozoa to undergo follicular fluid induced acrosome reaction. Neither chemical composition nor protein supplementation of capacitation media greatly affected motion parameters after 2 h incubation. Furthermore, chemical composition had only a small effect on the ability of spermatozoa to undergo the acrosome reaction upon exposure to follicular fluid. A higher proportion of spermatozoa underwent acrosome reaction after incubation in HSM (8% control (C); 28% follicular fluid) than in BWW (8% C, 17% follicular fluid) or Ham's F-10 (6% C, 19% follicular fluid). By contrast, protein source proved critical in determining acrosome reaction inducibility. Spermatozoa incubated in BSA-supplemented media showed a 4-fold increase in acrosomal discharge when exposed to follicular fluid (6% C, 22% follicular fluid) compared to controls while spermatozoa incubated in FCS were unable to undergo acrosome reaction (6% C, 6% follicular fluid). Simultaneous addition of FCS to BSA capacitation medium blocked acrosome reaction inducibility and the late addition of BSA, after sperm incubation in FCS, did not facilitate acrosome reaction. We propose that an inhibitor of sperm capacitation is present in FCS and therefore, the selection of optimum incubation conditions for spermatozoa may be of critical importance when evaluating or treating infertile patients.

Acrosome↗
PubMed1993

Acute hemorrhage in dogs: construction and validation of models to quantify blood loss.

We examined the ability of commonly used clinical parameters to quantify acute hemorrhage in dogs. Eight animals were bled 40 ml/kg body wt over 100 min. Ten hemodynamic and 20 blood laboratory parameters were obtained every 10 min to construct, with use of linear regression analysis, models that quantify blood loss. During model construction, the best indicator of quantity of hemorrhage was arterial base deficit [ABD; coefficient of variation (CV) 35%]. This model was more accurate (P < 0.05) than 27 others (CV range 43 to 63%) and similar to systolic (CV 40%) and mean (CV 40%) arterial pressures. In validation studies in 10 additional animals, our best models based on ABD and systolic and mean arterial pressures each unexpectedly showed a significant (P < 0.05) decrease in accuracy (CV 86, 57, and 60%, respectively) attributable to large baseline (before hemorrhage) variability among animals. To eliminate this variability, models based on changes from baseline measurements were investigated. The best predictor of change in blood volume was change in ABD (CV 27%). This model was significantly (P < 0.05) more accurate than any of 27 others (CV range 36 to 65%) and similar to change in venous base deficit and venous pH (each CV 31%). When validated, acid-base models such as ABD, venous pH, and arterial bicarbonate were the best predictors of volume change (CV range 28 to 40%). With the use of multivariate analysis, pairwise combinations of single parameter models (n = 465) improved prediction errors only minimally. In summary, most commonly used hemodynamic and blood indexes could not be validated as accurate measurements in quantifying hemorrhage. In contrast, changes in acid-base parameters were validated as moderately accurate predictors of blood volume changes and therefore may have utility in the assessment of patients with ongoing hemorrhage.

Acid-Base Equilibrium↗
PubMed1993

Leukocyte CD18 monoclonal antibody worsens endotoxemia and cardiovascular injury in canines with septic shock.

We investigated the effects of a murine monoclonal antibody directed against the canine leukocyte CD11/18 adhesion complex (MAb R15.7) in a canine model of septic shock. Awake 2-yr-old purpose-bred beagles were studied 7 days before and 1, 2, 4, and 10 days after intraperitoneal placement of an Escherichia coli-infected fibrin clot. Starting 12 h before clot placement, animals received 0.5-1 mg/kg iv every 12 h (4 doses total) of either MAb R15.7 (MAb group, n = 8) or, as controls, murine serum protein (n = 8). After infected clot placement, all animals received antibiotic (ceftriaxne, 100 mg.kg-1.day-1 for 4 days). Two of eight control animals and four of eight MAb animals died (P = 0.4). During the first 8 h after clot placement, MAb animals, compared with control animals, had greater (P < 0.06) increases in serum endotoxin levels and higher (P < 0.05) neutrophil counts. Day 1 after clot placement, MAb animals, compared with control animals, had decreased (P < 0.05) central venous pressure and arterial pH and increased (P < 0.05) arterial lactate. Day 2 after clot placement, MAb animals, compared with control animals, had decreased (P < 0.05) cardiac index and mean arterial pressure. In summary, MAb R15.7, although associated with increased neutrophil counts, worsened serum endotoxemia, acidosis, and cardiovascular function in this canine model of septic shock. These data suggest that in septic shock, antibody directed against this leukocyte membrane protein complex may be harmful, possibly via impairment of normal leukocyte function.

Acid-Base Equilibrium↗
PubMed1993

An analysis of police referrals to 10 psychiatric emergency rooms.

Data were collected on all psychiatric referrals to 10 emergency rooms in New York State during a 72-hour period in early December 1988. Overall, 30 percent of the 362 cases were brought by the police while the 10 emergency room percentages referrals varied from 10 to 53 percent. As compared with nonpolice referrals, police cases were as likely to be rated by clinicians as currently having psychotic symptoms, having a severe mental disorder, currently using substances, having a major mental illness diagnosis, and/or being referred to the emergency room for threatening to do harm or actually harming self. Police cases were more likely than nonpolice referrals to be male, to be referred to the emergency room due to impaired judgment or dangerous behavior to others, to be admitted to a psychiatric inpatient setting, and/or to have a longer length of stay in the emergency room. In addition, at municipal hospitals only, police referrals were more likely to be assaultive in the emergency room and/or not have payment resources. A logistic regression differentiated police cases from nonpolice cases on dangerous behavior to others and impaired judgment as reasons for referral, payment resources in municipal hospitals, and gender but not on any of the mental disorder variables. Policy implications for training and access to pretransport information and consultation are discussed.

Adult↗
PubMed1993

The effects of treatment with PIXY321 (GM-CSF/IL-3 fusion protein) on human polymorphonuclear leukocyte function.

During a phase I trial of the genetically engineered hematopoietic growth factor PIXY321 (granulocyte-macrophage colony-stimulating factor/interleukin-3 [IL-3] fusion protein), we examined the effects of PIXY321 treatment on human polymorphonuclear leukocyte (PMN) locomotive, respiratory burst, and phagocytic responses. PIXY321 treatment was associated with transient suppression of both unstimulated locomotion and chemotaxis responses to multiple stimuli, as well as significant transient enhancement of formyl peptide-stimulated H2O2 production. No effects on opsonic phagocytosis of Staphylococcus aureus were observed. In vitro exposure of control PMN to PIXY321 resulted in suppression of unstimulated locomotion/chemotaxis and enhancement of formyl peptide-stimulated H2O2 production but had no effects on phagocytosis. When patient cells were exposed in vitro to PIXY321 during treatment, suppression of chemotaxis and enhancement of H2O2 production were observed before PIXY321 treatment, but these effects diminished during treatment. The in vivo and in vitro exposure effects of PIXY321 treatment on PMN function are similar to those of the parent molecule, granulocyte-macrophage colony-stimulating factor (GM-CSF).

Adult↗
PubMed1992

Epidemiology of thrombocytopenia in HIV infection.

Thrombocytopenia is a known complication of human immunodeficiency virus Type-1 (HIV-1) infection, and more data need to be collected on its frequency, severity, and clinical sequelae. We determined the frequency of thrombocytopenia and its relationship to other HIV infection characteristics from a review of records of 1004 HIV-infected patients attending two outpatient clinics in Washington, D.C. The self-reported sources of HIV-1 exposure were male homosexual activity (68%), bisexual activity (10%), heterosexual activity (6%), and intravenous drug use (15%). Fifty-nine percent of the individuals were white, 37% were black and 94% were male. Fifteen percent had AIDS. Thrombocytopenia occurred more frequently in subjects with AIDS (21.2%) than in HIV-infected individuals who did not fit clinical criteria for AIDS (9.2%) (p less than 0.001). Patients with few CD4-positive cells and an advanced stage of disease were more likely to have low platelet counts: 30% with an absolute CD4 cell count lower than 200/mm3 vs 8% with CD4 counts between 200 and 500 (p less than 0.00001), and 18.5% with Stage IV disease compared to 7.6% in Stage II (p less than 0.001) had platelet counts less than 150,000/mm3. Thrombocytopenia was more frequent in white males and older subjects. Although subjects infected by heterosexual exposure had a lower frequency of thrombocytopenia, intravenous drug users and homosexual men exhibited similar frequencies of thrombocytopenia. Of all subjects with platelet counts less than 50,000/mm3, 40% reported bleeding and 1 died of an intracranial hemorrhage. Thrombocytopenia occurs frequently in HIV-infected people, primarily in those with AIDS, low CD4 cell numbers, and advanced stages of diseases.

Acquired Immunodeficiency Syndrome↗
PubMed1992

Tumor necrosis factor challenges in canines: patterns of cardiovascular dysfunction.

Three groups of conscious canines were given different intravenous doses of human recombinant tumor necrosis factor (TNF) over 1 h, and the resulting cardiovascular abnormalities were examined for 10 days. As TNF dose increased [0 (controls), 30, 60, and 120 micrograms/kg body wt], the number of deaths increased (P less than 0.025; 0 of 6, 1 of 8, 4 of 8, number of deaths in each group, respectively). In all three groups receiving TNF, the mean left ventricular ejection fraction (LVEF) at 2 h after infusion decreased (P less than 0.003) compared with controls. The group receiving the highest dose of TNF (120 micrograms/kg body wt) had the greatest decrease (P less than 0.05) in LVEF from 0 to 2 h. At 8 h, all three groups receiving TNF had similar LVEF. In these three groups, other multiple measures of LV function at 8 h showed significant and similar decreases in cardiac contractility compared with controls. From 24 to 240 h, however, the time required for cardiac performance (LVEF) to return to normal was dose dependent (30 less than 60 less than 120 micrograms/kg body wt; P less than 0.05). Canines receiving the lowest dose of TNF had near normal cardiac function (LVEF) at 24 h, whereas canines receiving the highest dose had persistent cardiac abnormalities at 240 h. Thus, at 8 h, the severity of cardiac dysfunction is independent of TNF dose, but the rate of onset and the duration of cardiac abnormality are markedly dependent of dose.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

Leukocyte CD11b/18 antigen-directed monoclonal antibody improves early survival and decreases hypoxemia in dogs challenged with tumor necrosis factor.

This study examined the effect of monoclonal antibody (MAb) directed against leukocyte CD11b/18 glycoprotein complex (904MAb) on cardiopulmonary injury induced by tumor necrosis factor (TNF), and death. Eighteen 2-yr-old, purpose-bred beagles with chronic tracheostomies were challenged with TNF (60 micrograms/kg of body weight) intravenously. Nine of 18 animals were treated with 0.5 to 1.0 mg/kg of body weight 904MAb intravenously 45 min before and 12, 36, and 48 h after TNF infusion. Serial femoral and pulmonary arterial catheter hemodynamics, blood gas analysis, and radionuclide cineangiographic left ventricular ejection fractions (EF) were done before and after a fluid challenge. Serial bronchoalveolar lavages (BAL) with cell and protein analysis also were performed using the chronic tracheostomies. Compared with animals given TNF alone, animals treated with 904MAb did not differ in overall survival (TNF alone, 2/9; 904MAb, 3/9); however, the group of animals treated with 904MAb had significantly (p less than 0.01) fewer deaths within the first 30 h of TNF challenge. At 4 h after TNF challenge, all animals had significantly (p less than 0.05) reduced PaO2 after fluid challenge; however, animals given 904MAb (compared with animals given TNF alone) had significantly (p less than 0.05) smaller reductions in PaO2. Throughout the study, animals given 904MAb before TNF or TNF alone had similar changes in cardiac index, mean arterial pressure, EF, and BAL protein and neutrophil concentration. Thus, MAb directed against the leukocyte CD11b/18 glycoprotein complex prolonged survival and reduced the hypoxemia occurring after TNF challenge, but this antibody did not improve overall survival or cardiopulmonary function.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

The relationship between patient-staff ratio and reported patient incidents.

The relationship between patient-staff ratio and the prevalence of patient incidents, such as assaults, fighting, suicides, falls, and abuse of patients by staff, was examined at an urban inpatient psychiatric center. Stepwise logistic regression was used to analyze 5,375 shifts in 14 high-incident wards representing five types of inpatient services; sample periods from three different years were examined. At least one incident occurred during 411 shifts (7.6 percent). More incidents occurred on the day shift and on two specific wards, confirming previous findings of a relationship between incidents and time of day as well as patient characteristics and milieu. However, no relationship between patient-staff ratio and the occurrence of incidents was found. This finding suggests that small increases in the number of ward staff may not reduce the number of patient incidents.

Circadian Rhythm↗
PubMed1992

Factors predicting referral to inpatient or outpatient treatment from psychiatric emergency services.

Dispositional decisions in ten psychiatric emergency rooms in New York State were examined using logistic regression. Variables influencing recommendations for inpatient or outpatient psychiatric treatment were fairly consistent across the hospitals. All terms used in the regression model were interactions formed from five variables: dangerous behavior as a reason for referral, severity of the mental disorder, the hospital where the patient presented, current signs of psychosis, and a diagnosis of major mental illness. A sixth variable, assaultive behavior in the emergency room, also influenced disposition decisions but could not be considered in the model because all patients with that characteristic were referred for inpatient treatment. A model of disposition decisions based on interactions of variables may be especially powerful because it captures the dynamic combination of factors clinicians encounter.

Adult↗