A comparison of clozapine and haloperidol in hospitalized patients with refractory schizophrenia. Department of Veterans Affairs Cooperative Study Group on Clozapine in Refractory Schizophrenia

Olanzapine versus haloperidol in the treatment of schizophrenia and other psychotic disorders: quality of life and clinical outcomes of a randomized clinical trial

BACKGROUND

Little information is available on the impact of the atypical antipsychotic olanzapine on quality of life (QOL). A 6-week, double-blind randomized multicenter trial, with a long-term extension, was conducted to evaluate the clinical efficacy and QOL of olanzapine and haloperidol in treating schizophrenia and other psychotic disorders.

METHODS

A total of 828 outpatients provided QOL data. Study patients were aged greater than 18 years with a DSM-III-R diagnosis of schizophrenia, schizophreniform disorder, or schizoaffective disorder and baseline BPRS (items scored on 0-6 scale) total scores, > or = 18 were randomized to 6 weeks of treatment with olanzapine 5 to 20 mg/day or haloperidol 5 to 20 mg/day. Patients entered a 46-week double-blind extension if they demonstrated minimal clinical response and were tolerant to study medication. The Quality of Life Scale (QLS) and SF-36 Health Survey were used to evaluate QOL.

RESULTS

During the 6-week acute phase, olanzapine treatment significantly improved BPRS total (p = 0.004), PANSS total scores (p = 0.043), QLS total (p = 0.005), intrapsychic foundations (p < 0.001) and interpersonal relations scores (p = 0.036), and SF-36 mental component summary scores (p < 0.001) compared with haloperidol. During the extension phase, olanzapine treatment significantly improved PANSS negative scores (p = 0.035) and improved QLS total (p = 0.001), intrapsychic foundations (p < 0.001), and instrumental role category scores (p = 0.015) versus haloperidol treatment. Significantly more haloperidol patients discontinued treatment due to adverse events during the acute and extension phases (p = 0.041 and p = 0.014, respectively). Changes in QLS total and MCS scores were associated with changes in clinical symptoms, depression scores and extrapyramidal symptoms.

CONCLUSIONS

Olanzapine was more effective than haloperidol in reducing severity of psychopathology and in improving QOL in patients with schizophrenia and other psychotic disorders. The QOL benefits of olanzapine, although modest, may be important for long-term treatment.

Conformationally constrained butyrophenones with mixed dopaminergic (D(2)) and serotoninergic (5-HT(2A), 5-HT(2C)) affinities: synthesis, pharmacology, 3D-QSAR, and molecular modeling of (aminoalkyl)benzo- and -thienocycloalkanones as putative atypical antipsychotics

A series of novel conformationally restricted butyrophenones (2-(aminoethyl)- and 3-(aminomethyl)thieno- or benzocycloalkanones bearing (6-fluorobenzisoxazolyl)piperidine, (p-fluorobenzoyl)piperidine, (o-methoxyphenyl)piperazine, or linear butyrophenone fragments) were prepared and evaluated as atypical antipsychotic agents by in vitro assays of affinity for dopamine receptors (D(1), D(2)) and serotonin receptors (5-HT(2A), 5-HT(2C)) and by in vivo assays of antipsychotic potential and the risk of inducing extrapyramidal side effects. Potency and selectivity depended mainly on the amine fragment connected to the cycloalkanone structure. As a group, compounds with a benzisoxazolyl fragment had the highest 5-HT(2A) activities, followed by the benzoylpiperidine derivatives; in general, alpha-substituted cycloalkanone derivatives were more active than the corresponding beta-substituted congeners. CoMFA (comparative molecular field analysis) and docking studies showed electrostatic, steric, and lipophilic determinants of 5-HT(2A) and D(2) affinities and 5-HT(2A)/D(2) selectivity. The in vitro and in vivo pharmacological profiles of N-[(4-oxo-4H-5, 6-dihydrocyclopenta[b]thiophene-5-yl)ethyl]-4-(6-fluorobenzisox azol-3 -yl)piperidine (23b, QF 0510B), N-[(4-oxo-4,5,6, 7-tetrahydrobenzo[b]thiophene-5-yl)ethyl]-4-(6-fluorobenzisoxazol- 3-y l)piperidine (24b, QF 0610B), and N-[(7-oxo-4,5,6, 7-tetrahydrobenzo[b]thiophene-6-yl)ethyl]-4-(6-fluorobenzisoxazol- 3-y l)piperidine (29b, QF 0902B) suggest that they may be effective antipsychotic drugs with low propensity to induce extrapyramidal side effects.

Evidence of clozapine's effectiveness in schizophrenia: a systematic review and meta-analysis of randomized trials

OBJECTIVE

The purpose of this study was to evaluate all available trial-based evidence on the effectiveness of clozapine in schizophrenia as compared with conventional neuroleptics.

METHOD

All randomized, controlled trials comparing clozapine with a conventional neuroleptic in which there was satisfactory concealment of patients' treatment allocation were located through electronic searches in all languages of several databases and through contacting authors of recent trials as well as the manufacturer of clozapine. At least two independent reviewers assessed trials for inclusion in the study and extracted data for meta-analysis.

RESULTS

The review included 2,530 randomly assigned participants in 30 trials, most of them short-term. Clozapine-treated patients showed more clinical improvement and experienced significantly fewer relapses during treatment, although the risk of blood dyscrasias in long-term treatment may be as high as 7%. Scores on symptom rating scales showed greater improvement among clozapine-treated patients, who were also more satisfied with their treatment. However, there was no evidence that the superior clinical effect of clozapine is reflected in levels of functioning; on the other hand, global functional and pragmatic outcomes were frequently not reported. Clinical improvement was most pronounced in patients with treatment-resistant illness.

CONCLUSIONS

This meta-analysis confirms that clozapine is more effective than conventional neuroleptics in reducing symptoms of patients with both treatment-resistant and nonresistant schizophrenia. Future trials should be long-term pragmatic community trials or should address the effectiveness of clozapine in special patient populations. An international standard set of outcomes, including pragmatic assessments of functioning, would greatly enhance the comparison and summation of trials and future assessments of effectiveness.

Cost-effectiveness of atypical antipsychotics in chronic schizophrenia

It is nearly a decade since the first atypical antipsychotic, clozapine, was launched in the UK. There are now several other similar drugs on the market. They are all more expensive than traditional antipsychotics and the question of whether they are a cost-effective use of scare NHS resources is an important one. This article reviews the evidence in the area of treatment-resistant schizophrenia.

Schizophrenia

Schizophrenia is among the most severe and debilitating of psychiatric disorders. Diagnosis is currently by criterion-based systems, including positive (eg, hallucinations and delusions) and negative (eg, avolition and alogia) symptoms. The importance of negative symptoms in the course and outcome of the illness is increasingly being studied. Current research seeks to detect causal mechanisms in schizophrenia through studies of neural connectivity and function, as well as models of genetic transmission, such as polygenic models of inheritance in genetic research. Potential genes have been identified that may confer vulnerability to the illness, perhaps in conjunction with environmental factors. Neuroimaging research with magnetic resonance imaging and positron emission tomography has investigated differences in volumes and functional dysregulation in specific neural subregions. Areas studied include the frontal and temporal cortex, the hippocampus, the thalamus, and the cerebellum. Despite these advances, treatment of symptoms and psychosocial and cognitive impairments remains only partially successful for many patients.

Review of methods to determine VA health care costs

BACKGROUND

Estimates of health care cost are needed to conduct cost-effectiveness research at the facilities operated by the US Department of Veterans Affairs.

METHODS

The medical literature was searched for VA studies to characterize different cost methods and identify their advantages and disadvantages.

RESULTS

Different methods are appropriate for different studies. Analysts who wish to capture the effect of an intervention on resources used in a health care encounter may wish to create a detailed pseudo-bill by combining VA utilization data with unit costs from the non-VA sector. If a cost function can be estimated from non-VA data, VA costs may be determined more economically from a reduced list of utilization items. If the analysis involves a new intervention or a program that is unique to VA, direct measurement of staff time and supplies may be needed. It is often sufficient to estimate the average cost of similar encounters, for example, the average of all hospital stays with the same diagnosis and same length of stay. Such estimates may be made by combining VA cost and utilization data bases and by applying judicious assumptions.

CONCLUSIONS

Assumptions used to estimate costs need to be documented and tested. VA cost-effectiveness research could be facilitated by the creation of a universal cost data base; however, it will not supplant the detailed estimates that are needed to determine the effect of clinical interventions on cost.

Health care costs of therapy-refractory schizophrenic patients treated with clozapine: a study in a community psychiatric service in Italy

This study evaluates the utilization of clozapine in the treatment of therapy-refractory schizophrenia in terms both of patterns of care and of health care costs in a community psychiatric service in Italy. Data covering the year prior to commencing clozapine and the year following the initiation of the therapy were collected. Clinical outcome was assessed by means of the Clinical Global Impression (CGI) and Global Assessment of Functioning (GAF) scales. Cost analysis followed a two-step procedure: (i) to record all health care services provided to patients and (ii) to assign a monetary value to each service. Three of the 15 patients enrolled in the study dropped out before the end of the 12-month period of therapy. Considering the 12 patients on clozapine treatment for at least 1 year, clinical improvements are associated with a substantial modification of the pattern of care. While patients in the pre-clozapine period were mainly managed in hospital settings, patients on clozapine were prevalently placed in the community and participated in intensive rehabilitative programmes. The higher costs of drug therapy and community services in the post-clozapine period were more than offset by the lower costs of acute hospital care.

Risperidone and clozapine combination for the treatment of refractory schizophrenia

Clozapine is the most widely used antipsychotic drug for the treatment of refractory schizophrenia. Here we report the case of two residual schizophrenic patients refractory to conventional antipsychotics who showed a poor response to atypical antipsychotics. The combination of risperidone and clozapine produced a noticeable improvement in the patients' clinical status and a shortening of the treatment response latency.

Inadequate prescription-drug coverage for Medicare enrollees--a call to action

In summary, most low-income elderly and disabled persons lack coverage for important medications, resulting in avoidable deterioration of health among those with chronic illnesses and use of expensive institutional services. Rapidly escalating drug costs, more restrictive drug-coverage policies, and a dramatic increase in the population of elderly and disabled persons will exacerbate these problems. With the current budget surplus, as well as bipartisan concern about health care needs and public concern about drug costs and coverage, it is time to act responsibly and aggressively. We recommend a national replication of the best features of state pharmacy-assistance programs in a federal-state insurance program for low-income Medicare enrollees, either alone or in combination with expanded Medicare coverage. Such a program will reduce the current inequitable situation in which the most vulnerable patients have the least access to medications, with serious medical and economic consequences.

Sustained long-term improvement with clozapine in schizophrenia

The present paper reports the long-term use of clozapine in a prospective sample of 46 chronic schizophrenics. In six months, 21 subjects had been excluded for a number of reasons. In four of them the reasons for exclusion were related to lack of response or adverse effects. The median daily clozapine dose was 400 mg in the remaining 25 patients. As a whole, there were remarkable improvements in core dimensions of psychopathology, global cognitive status, and level of functioning. We confirmed that clozapine is effective in a subgroup of schizophrenics with the severest forms of the disease. If tolerated after the first few months it leads to progressive gains in several domains of behavior. Clozapine should be tried in every patient with schizophrenia in whom positive symptoms, disorganization, or bizarre behavior are a matter of incapacitation despite efforts to keep them under control with other drugs.

Comparative efficacy of olanzapine and haloperidol for patients with treatment-resistant schizophrenia

BACKGROUND

There is relatively little information regarding the efficacy of newer atypical antipsychotic drugs for patients with schizophrenia who are treatment-resistant to neuroleptic agents. Several lines of evidence suggest that a clinical trial of olanzapine in this population is warranted.

METHODS

A subpopulation of patients (n = 526) meeting treatment-resistant criteria selected from a large, prospective, double-blind, 6-week study assessing the efficacy and safety of olanzapine and haloperidol were examined. Both last-observation-carried-forward (LOCF) and completers (observed cases) analyses were conducted.

RESULTS

Olanzapine demonstrated significantly greater mean improvement from baseline in Positive and Negative Syndrome Scale (PANSS) negative symptoms, comorbid depressive symptoms assessed by the Montgomery-Asberg Depression Rating Scale, akathisia as measured by Barnes Akathisia Scale, and extrapyramidal symptoms as measured by Simpson-Angus Extrapyramidal Rating Scale with both LOCF and completers analyses. In addition, olanzapine was significantly superior to haloperidol for Brief Psychiatric Rating Scale total (p = .006), PANSS total (p = .005), and PANSS positive symptoms (p = .017) in completers of the 6-week study. Significantly greater response rates were observed in olanzapine-treated (47%) than haloperidol-treated (35%) patients in the LOCF analysis (p = .008), but significance was not reached in the completers analysis (p = .093). Mean doses (+/- SD) of olanzapine and haloperidol were 11.1 +/- 3.4 mg/day and 10.0 +/- 3.6 mg/day, respectively.

CONCLUSIONS

Olanzapine was superior to haloperidol for key symptom domains and parkinsonian side effects. Implications of these data for the therapeutics of this severely ill subgroup are discussed.

Atypical antipsychotics: Part II: Adverse effects, drug interactions, and costs

OBJECTIVE

To compare the adverse effects, drug interactions, and costs of conventional and atypical agents, and to provide a summary of therapeutic guidelines. Part I compared the pharmacology, pharmacokinetics, and efficacy of atypical and conventional agents.

DATA SOURCES

Information was retrieved from a MEDLINE English-language literature search from June 1986 to June 1998 and by review of references. Indexing terms included atypical antipsychotics, neuroleptics, clozapine, risperidone, olanzapine, sertindole, quetiapine, and ziprasidone.

STUDY SELECTION

Comparative studies were selected when possible; placebo-controlled studies were included when data were limited on newer atypical antipsychotics.

DATA EXTRACTION

Emphasis was placed on properly designed clinical trials that assessed dosage, expanded efficacy, enhanced adverse effect profile, and cost.

DATA SYNTHESIS

Significant adverse effects are agranulocytosis with clozapine, dose-dependent extrapyramidal side effects (EPS) with risperidone, and neuroleptic malignant syndrome with clozapine and risperidone. Clinically relevant drug interactions may occur with clozapine-lorazepam, clozapine-fluvoxamine, and sertindole-quinidine. Newer atypical agents have high acquisition costs but may reduce noncompliance and rehospitalization rates.

CONCLUSIONS

Risperidone or olanzapine are recommended as first-line agents for schizophrenia due to accumulating controlled trials and clinical experience. Quetiapine should be considered with partial response or if EPS develop, and clozapine is an option with treatment-refractory patients. Atypical agents may contribute to a better quality of life, but conventional neuroleptics are the first choice for strictly cost considerations.

Efficacy and extrapyramidal side-effects of the new antipsychotics olanzapine, quetiapine, risperidone, and sertindole compared to conventional antipsychotics and placebo. A meta-analysis of randomized controlled trials

The objective of this meta-analysis is to summarize the efficacy and tolerability of the new antipsychotics risperidone, olanzapine, sertindole and quetiapine in schizophrenia compared to placebo and conventional antipsychotics. The main results are: (1) All of the 4 new drugs are more effective than placebo, but the magnitude of the effect is only moderate [mean effect size, r, of all antipsychotics vs. placebo = 0.25, with a 95% confidence interval (CI) = 0.22-0.28, n = 2477]. (2) According to the studies published to date, sertindole and quetiapine are as effective as haloperidol, and risperidone and olanzapine are slightly more effective than haloperidol in the treatment of global schizophrenic symptomatology. (3) With respect to negative symptoms, all new antipsychotics are more effective than placebo. However, contrary to widespread opinion, so is the 'conventional' antipsychotic haloperidol. Risperidone and olanzapine are slightly superior, sertindole is as effective and--according to the only study fully published to date--quetiapine is even slightly less effective than haloperidol in this regard. (4) All new antipsychotics are associated with less frequent use of antiparkinson medication than haloperidol, with risperidone appearing to have a slightly less favourable EPS-profile than the other new antipsychotics. The methodological limitations of this review, the generalizability of the results and expectations from future research are discussed.

Pharmacological treatment of schizophrenia resistant to first-line treatment: a critical systematic review and meta-analysis

Schizophrenia resistance to conventional antipsychotics is a common phenomenon. In 5-25% of cases, satisfactory treatment response is not achieved, and intolerance to conventional antipsychotics occurs in 5-20% of patients. Numerous reasons for refractoriness have been proposed. However, up to now only a few pharmacological agents have been found useful in the treatment of schizophrenia resistant to conventional antipsychotics. This paper critically reviews quality-assessed trials on the pharmacological treatment of refractory schizophrenia. Randomized blinded trials of conventional antipsychotics at high doses, atypical antipsychotics, lithium, propranolol, and agents not traditionally used in the treatment of schizophrenia are reviewed. On the basis of the methodologically sound studies included, we conclude that only clozapine has proved to be clinically effective in the treatment of refractory schizophrenia. In the short term, the odds ratio for clinical improvement on clozapine treatment when compared to conventional treatment is calculated to be 2.4 (95% confidence interval [CI] 1.7-3.5) and the number of patients needed to treat (NNT) is 7 (95% CI 5-13). In single inconclusive trials, olanzapine and risperidone have been found as effective as clozapine. In order to establish the usefulness of other pharmacological treatments, more randomized clinical trials are needed.

The pharmaco-economics of atypical antipsychotics

Atypical antipsychotics are claimed to show advantages in efficacy and tolerability when compared with older, typical drugs. However, the purchase cost of atypicals far exceeds that of typical drugs. Pharmaco-economic evaluations of the use of atypical agents are used, in essence, to determine whether or not the benefit gained by using atypicals is greater than the extra cost of their acquisition. Several forms of pharmaco-economic evaluation have been developed, but none provides definitive, unarguable findings. In psychiatry, the most commonly used method is the mirror-image technique, which retrospectively compares costs and outcomes before and after the use of a particular drug. Despite the large number of phamacoeconomic evaluations undertaken and published, the cost-effectiveness of atypical drugs remains unproven. Data relating to clozapine are the most compelling, but they remain ultimately equivocal. However, ethical considerations may prevent conclusive research being conducted. Some data support the cost-effectiveness of olanzapine and risperidone, but, again, the overall picture is far from clear. Little or nothing is known of the pharmaco-economics of other atypicals. Further research is needed before any atypical can be said to be cost-effective.

Clinical outcome to clozapine treatment in chronic psychiatric inpatients

1. A review of the medical records in a state psychiatric hospital was conducted to evaluate the clinical efficacy of the atypical antipsychotic, clozapine. 2. Using the Brief Psychiatric Rating Scale (BPRS), four groups of schizophrenic inpatients (n = 59) were operationally defined: Nonresponders (< 20% decrease from pre-drug baseline); Short-term Pharmacological Responders (20% decline, but not sustained); Long-term Pharmacological Responders (maintained a 20% decline) and Clinical Responders (maintained a 20% decline and achieved a BPRS < or = 36; the criterion of Kane et al. 1988). 3. There were 7 NRs, 13 STPRs, 21 LTPRs and 18 CRs 4. The STPR, LTPR and CR groups improved significantly within the first month of treatment and reached a 20% decrease in BPRS by 3 months. CRs required 5 months to attain a BPRS < or = 36. These criteria were reached at the same average doses (about 300-400 mg/day). 5. The proportion of CRs (30%) in this retrospective, naturalistic study, is remarkably close to the results of the definitive study by Kane et al. 1988. These results are also consistent with many of the controlled research studies of clozapine in hospitalized, treatment refractory psychiatric patients.

Predictors of differential response to clozapine and haloperidol. Veterans Affairs Cooperative Study Group on Clozapine in Refractory Schizophrenia

BACKGROUND

We sought to identify baseline predictors of response to clozapine.

METHODS

Data were from a 15-site randomized clinical trial comparing clozapine and haloperidol in hospitalized patients with refractory schizophrenia (n = 423). Three-month outcomes were analyzed with the full sample (n = 368 due to attrition). Because of crossovers, analyses of 12-month outcomes were conducted with crossovers excluded (n = 291). Clinical predictors included age, race, diagnosis (current substance abuse, paranoid subtype of schizophrenia, or depressive syndrome), severity of symptoms, quality of life, age at onset of schizophrenia, extrapyramidal symptoms, and VA compensation payment. Multiple regression analysis was used to examine the interaction of treatment condition and each of these variables in predicting outcomes for symptoms, quality of life, side effects, and days hospitalized.

RESULTS

Patients with higher quality of life at baseline (p = .04) and higher symptoms (p = .02) had relatively smaller declines in hospital days at 6 months. In the 12-month sample patients with higher levels of symptoms had greater symptom reductions at 12 months (p = .03) and greater improvement in quality of life (p = .004).

CONCLUSIONS

Although high levels of symptoms were associated with greater improvement on clozapine, these findings are not robust enough to suggest that any specific, clinically defined subgroup of refractory patients should be preferentially targeted for clozapine treatment.

Novel antipsychotics and patient care in state hospitals

OBJECTIVE

To review and highlight the opportunities and challenges of pharmacologic advances in the use of antipsychotics for the state hospital system.

METHODS

A critical review was performed of studies published either as articles or abstracts, on the use of novel antipsychotics, particularly as they relate to the patient population within the state mental hospital system.

FINDINGS

The recent availability of new antipsychotic medications within state facilities has resulted in more progressive treatment, reduced recidivism (and consequently cost savings), and preliminary evidence of preferential and superior treatment response in specific patient subgroups (e.g., those with aggression). At the same time, inpatient pharmacy budget increases and uncertainty in guiding the use of novel antipsychotics have influenced the availability of these agents in state hospitals.

CONCLUSIONS

State hospital services have, by and large, embraced the developments in pharmacotherapy of schizophrenia. Optimal use of these new agents in this population requires additional information on their relative efficacy in specific patient subgroups.

[Economic perspectives in the care and treatment of patients diagnosed with schizophrenia]

OBJECTIVE

To consider the main problems associated with care and treatment of patients with diagnosis of schizophrenia in the light of the more recent literature of the economic aspects of this pathology.

METHOD

An analysis of the literature related to the social costs of schizophrenia, the economic analysis of different health-care models, and the evaluation of the costs of antipsychotic treatments has been carried out.

RESULTS

Schizophrenia is a pathology creating huge social costs. The health costs associated with the care of schizophrenia take up a significant amount of the resources of healthcare systems in the principal industrialised countries. Indirect costs, due mainly to the patients' exclusion from work, exceed the direct costs of treatment. In those countries where community care has been supported by a real organisational effort to create community and residential services, it has proved to be a cost-effective solution compared with psychiatric hospital-based care and provides patients and family members with better results. The introduction of new antipsychotic drugs and the development of psychosocial support could represent the means of encouraging new healthcare strategies.

CONCLUSIONS

From an economic perspective, the organisation, technological means, and strategies which would allow the available resources to be invested in a rational way must be considered. Consideration of these issues appears to be unavoidable today, not only for the administrators and the policy makers but also for mental health service professionals.

Do atypical antipsychotic medications favorably alter the long-term course of schizophrenia?

Schizophrenia is characterized by the greatest degree of clinical deterioration in the first decade following onset of psychosis; in fact, deterioration begins even prior to the onset of frank psychotic symptomatology. While somewhat controversial, it appears that effective early antipsychotic treatment might limit the extent of such deterioration. The newer, atypical antipsychotics such as clozapine, risperidone, olanzapine and quetiapine appear to have antipsychotic efficacy at least equal to the traditional neuroleptics, but with a much more favorable side effect profile. Clozapine is also effective in treating neuroleptic-refractory schizophrenic patients. Data suggest that in comparison to conventional agents, treatment with atypical antipsychotics may be associated with a more benign course of schizophrenic illness. Whether these atypical antipsychotics are associated with greater efficacy in limiting clinical deterioration in schizophrenic illness than traditional neuroleptics is, however, unclear. The following questions will be addressed in this paper: (i) Do atypical antipsychotics differ from traditional neuroleptics in modifying the natural course of symptomatology in schizophrenic illness? (ii) Do atypical antipsychotics differ from typical neuroleptics in modifying the natural course of neurobiological and cognitive abnormalities in schizophrenic illness? (iii) Do atypical antipsychotics differ from typical neuroleptics in modifying the natural course of psychosocial dysfunction in schizophrenic illness? (iv) Are there differences between typical and atypical antipsychotics with regard to their effects on the cost of care and resource utilization? The implications of the answers to these questions for the long-term treatment of schizophrenia will be discussed.

Cooperative studies in health services research in the Department of Veterans Affairs

The Department of Veterans Affairs, through its Cooperative Studies Program, has a long history of conducting large-scale, multihospital biomedical clinical trials. The agency's Health Services Research and Development Service, although newer, has a distinguished record of mainly single-site research into the organization, delivery, and financing of health services. In 1990, a joint program was initiated to conduct multicenter studies in health services research. This article describes the studies developed in the new program and the research design issues encountered in planning them. Identification of the patient population, specification and measurement of the intervention, and description of the control group, as well as attention to the unit of randomization and analysis, outcome variables and choice of effect size, data quality, and ethical considerations are among the important issues related to the design of these studies and future studies in health services.

Pharmacoeconomics of the new antipsychotics for the treatment of schizophrenia

Inevitably, the greater availability of more costly antipsychotic medications has resulted in attempts to regulate the use of these agents. Early objections over the cost of treatment with clozapine or risperidone have in part been mollified by preliminary statistics on the cost effectiveness of these agents. However, this issue is complex and requires careful consideration of pharmacoeconomic principles in the development and clinical distribution of novel antipsychotics. Future cost-effectiveness studies need to consider a balance of public and private perspectives. These studies should be conducted in several settings, preferably also within the context of broader, multimodal treatment intervention strategies.