PubMed Health⌕ Search

Biomedical subjects

E M Laska

Publications and source records attributed to E M Laska.

12 recordsLinked to original sources
PubMed1992

Nonparametric estimation and testing in a cure model.

Nonparametric generalized maximum likelihood product limit point estimators and confidence intervals are given for a cure model with random censorship. One-, two-, and K-sample likelihood ratio tests for inference on the cure rates are developed. In the two-sample case its power is compared to the power of several alternatives, including the log-rank and Gray and Tsiatis (1989, Biometrics 45, 899-904) tests. Implications for the use of the likelihood ratio test in a clinical trial designed to compare cure rates are discussed.

Biometry↗
PubMed1991

Importance of pharmacologic control in PET studies: effects of thiothixene and haloperidol on cerebral glucose utilization in chronic schizophrenia.

This study compares the effects of two neuroleptic drugs with different pharmacologic characteristics (thiothixene and haloperidol) on cerebral glucose utilization in chronic schizophrenic inpatients. Positron emission tomographic (PET) scans were obtained from all subjects in a neuroleptic-free condition and again after 4-6 weeks of neuroleptic treatment. Eight subjects were treated with thiothixene and 12 with haloperidol. Thiothixene and haloperidol had different metabolic effects. For example, all thiothixene-treated subjects showed increased whole brain glucose utilization; all but one haloperidol-treated subject showed decreased utilization. Different patterns of relative prefrontal and striatal metabolism were also observed. These results highlight the importance of controlling for the effects of neuroleptic treatment and indicate the difficulty of interpreting data from studies with complex or poorly defined drug regimens.

Adult↗
PubMed1989

Testing whether an identified treatment is best.

We consider the problem of testing whether an identified treatment is better than each of K treatments. Suppose there are univariate test statistics Si that contrast the identified treatment with treatment i for i = 1, 2,...., K. The min test is defined to be the alpha-level procedure that rejects the null hypothesis that the identified treatment is not best when, for all i, Si rejects the one-sided hypothesis, at the alpha-level, that the identified treatment is not better than the ith treatment. In the normal case where Si are t statistics the min test is the likelihood ratio test. For distributions satisfying mild regularity conditions, if attention is restricted to test statistics that are monotone nondecreasing functions of Si, then regardless of their covariance structure the min test is an optimal alpha-level test. Tables of the sample size needed to achieve power .5, .8, .90, and .95 are given for the min test when the Si are Student's t and Wilcoxon.

Biometry↗
PubMed1987

Analgesic efficacy of two ibuprofen-codeine combinations for the treatment of postepisiotomy and postoperative pain.

Our purpose was to compare the analgesic efficacy and safety of single oral doses of the combination of ibuprofen 400 mg plus codeine 60 mg and the combination of ibuprofen 200 mg plus codeine 30 mg with ibuprofen 400 mg alone, codeine sulfate 60 mg alone, and placebo. One hundred ninety-five patients with severe pain resulting from episiotomy, cesarean section, or gynecologic surgery completed a randomized, double-blind, stratified, parallel-group study. Patients were observed during a 4-hour period after medication. Based on the sum of the pain intensity differences (SPID), total pain relief (TOTPAR), and most of the hourly direct measures of pain and relief, both doses of the combination and ibuprofen 400 mg alone were statistically superior to placebo. Codeine 60 mg was statistically superior to placebo based on TOTPAR, the global ratings, and a few hourly measures. The mean effect of the combination of ibuprofen 400 mg plus codeine 60 mg was significantly superior to the mean effect of ibuprofen 400 mg alone 1/2, 1, and 2 hours after medication and to the mean effect of ibuprofen 400 mg alone and codeine 60 mg alone for SPID, TOTPAR, and other measures as well. The low-dose combination was significantly more effective than codeine 60 mg for a few hourly measures but was not significantly superior to ibuprofen 400 mg. Based on these findings it appears that the combination of ibuprofen 400 mg plus codeine 60 mg, particularly in the first few hours after medication, is more efficacious than its constituents.

Adult↗
PubMed1986

Comparative study of flurbiprofen, zomepirac sodium, acetaminophen plus codeine, and acetaminophen for the relief of postsurgical dental pain.

The relative analgesic efficacy and safety of single oral doses of 50 and 100 mg of flurbiprofen (Ansaid, Upjohn) were compared with 100 mg of zomepirac sodium, 650 mg of acetaminophen plus 60 mg of codeine, 650 mg of acetaminophen alone, and placebo in a randomized, double-blind, parallel-group study. A total of 182 patients entered the study with moderate pain from a third molar extraction and were evaluated for six hours. For many efficacy variables, all active treatments were significantly (p less than or equal to 0.05) more effective than placebo. The two doses of flurbiprofen gave approximately similar results, suggesting a plateau effect above 50 mg. With the exception of relief at one hour, there were no significant differences between zomepirac and either dose of flurbiprofen. However, the mean response with zomepirac was greater than with either 50 or 100 mg of flurbiprofen during the first four hours and lower during the last two hours. The analgesic effects of acetaminophen alone were not significantly different from acetaminophen in combination with codeine. At the first hour, acetaminophen plus codeine led to significantly better pain relief than did 100 mg of flurbiprofen. After the first hour, flurbiprofen resulted in greater mean scores than acetaminophen alone or acetaminophen plus codeine, and these differences were significant at the fifth and sixth hours. Five patients had adverse reactions while receiving acetaminophen, acetaminophen plus codeine, or placebo. There were no adverse effects with flurbiprofen or zomepirac.

Acetaminophen↗
PubMed1986

The correlation between blood levels of ibuprofen and clinical analgesic response.

A clinical trial comparing ibuprofen, 400, 600, and 800 mg, with aluminum ibuprofen, 400 mg, and placebo was conducted in patients with moderate or severe pain subsequent to third molar extraction. Pain intensity ratings and ibuprofen serum levels were obtained at baseline, 30 minutes, 1 hour, and hourly thereafter for 3 hours. Pain intensity ratings were also obtained at hours 4, 5, and 6. Serum levels at 1, 2, and 3 hours correlated significantly with the log dose of ibuprofen (r = 0.35, 0.49, and 0.48, respectively) and with global analgesic response as measured by the percentage of the sum of the pain intensity scores (r = 0.28, 0.34, and 0.26, respectively). However, possibly because of differences in drug formulation, the percentage of the sum of the pain intensity scores did not correlate significantly with log dose. The highest correlations were found between contemporaneous serum levels and pain intensity difference values, particularly at hour 1 (r = 0.54). Our results support the proposition that increased ibuprofen serum levels lead to increased analgesia.

Adolescent↗
PubMed1986

Combining multivariate bioassays.

Linear multivariate theory is applied to the problem of combining several multivariate bioassays. Results are an asymptotic test of the hypothesis of a common log relative potency; the maximum likelihood estimator of the common log relative potency; and an exact and asymptotic confidence interval estimator for log relative potency.

Analysis of Variance↗
PubMed1976

29. The Multi-State Information System for Psychiatric patients.

The Multi-State Information System for Psychiatric Patients (MSIS) is a computer based, clinical and administrative management information system used by numerous mental health programs and facilities for patient and program management. Structured forms are used for the collection of core information on patients, on services rendered, on affiliated agencies, and on fiscal and administrative processes. A variety of output reports and general retrieval techniques are being used to help administer and evaluate patient care programs, monitor clinical and program management functions, refer clients to other service agencies, and review individual cases, as well as for administrative functions such as cost finding, rate setting, billing, and inventory control. MSIS is currently field testing an automated problem-oriented psychiatric record, and a goal-oriented record to be used with the mentally retarded is under development.

Humans↗
PubMed1975

Matched-pairs study of reserpine use and breast cancer.

This paper reports on an analysis of psychiatric population. 55 female patients with breast cancer were matched with non-cancer patients on age, year of admission, psychiatric diagnosis, race, and religion. Reserpine use was examined for yearly use by each year preceding the diagnosis of breast cancer, by cumulative yearly use, and by other defined time periods. Regardless of the definition of reserpine user, there were no significant increased relative risks of breast cancer for those women on reserpine. There was a fairly low proportion of patients from each group who were on the drug in any given year, and a fairly wide range of total dosage received. Over half of the women used reserpine at some time during their hospital stay.

Aged↗
PubMedDate not supplied

An analytic approach to quantifying pain scores.

Statistical problems in clinical trials frequently involve fitting regression lines when the underlying data are categorical or ordinal response variables. Usually an ad hoc a priori quantification is used to assign values to these ordinal responses. For pain intensity data collected in analgesic trials, the usual approach is to set none equal to 0, mild equal to 1, moderate equal to 2, and severe equal to 3. While this scheme has been generally accepted, on the basis that for similar clinical trials reasonably similar results are obtained by different investigators, concern exists that the distances between pain scores are probably not equal. A method is presented for quantifying categorical responses so that the resulting scores maximize the simultaneous fit of the dose-response regression lines. The optimal scores derived by this technique may then be used in a bioassay analysis to estimate the relative potency of 2 compounds. As illustrative examples, this method was applied to data from 2 clinical trials and the results were compared to the usual method.

Analysis of Variance↗