The highly inappropriate calibrations of statistical significance.

Comments that an article had used the term "highly significant" to describe an empirical result. The author considers such a modifier to statistical significance is entirely inappropriate on 2 counts. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Modeling the effects of hydroxypropylcellulose in acetaminophen tablet formulation

The objective of the research described here was to develop a set of predictive models that would be used to show the performance of hydroxypropylcellulose as a pharmaceutical tablet binder. A statistically designed set of experiments was used to relate tablet formulation to functionality. It was found that the binder level affected both hardness and dissolution time. Useful predictive models were generated for tablet hardness and dissolution time as a function of the binder or binder-drug ratio. The optimal formulation can be predicted from this study, and will depend upon the combination of desired hardness and the dissolution time for a particular drug.     

Methodological versus empirical literature: Two views on casual acceptance of the null hypothesis.

Presents examples of casual acceptance of the null hypothesis in respected journals. This occurs when authors are unaware of the problems discussed in the methodology literature. The literature proposes 4 criteria for a null conclusion, concerning problems with the data, probability, power of the research design, and persuasion based on overall relationships. The problem of inappropriate null conclusions should be solved by more attention in research to overall relationships and replications. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Commitment to collaboration as a prerequisite for existential commonality in psychotherapy.

Discusses the theoretical justification for commitment to collaboration (CTC) in behavior therapy. It is noted that psychotherapy for outpatient clients with problems of personal adjustment ordinarily requires the client to accept major responsibility for success. However, the importance of personal CTC with the therapist has not been adequately justified theoretically for behavior therapy in which treatment is nominally based on the learning theories of Thorndike and Pavlov. CTC helps establish existential commonality of awareness and thought between client and therapist, thus increasing the probability that later therapist behaviors will influence both client cognitions and adaptive responses. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Validation of tablet dissolution method by high-performance liquid chromatography

Dissolution is a qualitative and quantitative tool that can provide valuable information about biological availability of a drug, as well as batch-to-batch consistency. It is considered one of the most important quality control tests performed on pharmaceutical dosage forms, and validation of dissolution methods is an important part of good manufacturing practices (GMP). Hydroxypropylcellulose (HPC) was formulated with acetaminophen (APAP) and hydrochlorothiazide (HCTZ). Dissolution methods and limits are reported in the USP/NF. Standard operating procedures (SOP) for the HP 8452A spectrophotometer and Vanderkamp 600/6010 Dissolution Tester were followed according to the GMP Manual. A dissolution method was developed for each formulation based on the above. The only discrepancy between high-performance liquid chromatography (HPLC) and standard dissolution testing occurred when comparing the results of the HPC/HCTZ formulation. The ultraviolet (UV) samples were filtered through a 10-μm filter, and the HPLC samples were filtered through a 0.2-μm filter. When the HPC/HCTZ samples were filtered through a 10-μm filter for both UV and liquid chromatography (LC), the results were equal. Filter pore size and area have a large effect on concentration of HPC/HCTZ. The smaller the pore size and the smaller the diameter of the filter, the more HPC/HCTZ is filtered out. HCTZ has a greater tendency to interact with HPC in the filter than other active ingredients tested. HPC and HCTZ levels have little or no effect on the amount of HCTZ lost     

The fractionary psychology we try to give away.

Comments that the call by G. A. Miller (1969) and echoed by M. B. Smith (see record 1974-06996-001) to give psychology to the public, has not been consistently implemented by providing a unifying integration for the different approaches to the field, but that the public has been given a restricted and biased view. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Application of near-infrared spectroscopy in the pharmaceutical solid dosage form

Near-infrared (NIR) spectroscopy, one of the most rapidly growing methodologies in pharmaceutical analysis, has been used to analyze the pharmaceutical solid dosage form. The objective of this study was to examine the information that can be gathered from NIR spectroscopy and demonstrate the potential utility of the technique as an alternative to current methods of tablet performance testing. The tablet formulation included active drug (acetaminophen or theophylline), binder (hydroxyethylcellulose), filler (lactose, calcium sulfate, dibasic calcium phosphate dihydrate, or microcrystalline cellulose), and lubricant (magnesium stearate). The compression forces were varied from 5 to 25 kN. A Foss/NIRSystems scanning near-infrared spectrometer was used to measure the diffuse reflectance from the tablet surface. Each tablet was scanned on opposite sides to reduce the effects of positioning. First derivative and multiplicative scatter correction data treatments were explored. A calibration for compression force, independent of the filler, was developed. In addition, the spectra were able to distinguish among the fillers used. A comparison of these spectra with data collected earlier suggests that the technique could differentiate among drugs as well. Near-infrared diffuse reflection spectroscopy, when properly calibrated, can determine the compression force used to prepare a tablet. This measurement may be independent of the different active drugs or fillers used in the tablet formulations.     

The Evaluation of Fine-Particle Hydroxypropylcellulose as a Roller Compaction Binder in Pharmaceutical Applications

In solid dosage manufacturing, roller compaction technology plays an important role in providing cost control and a quality product. The objective of this study was to evaluate the effectiveness of fine-particle hydroxypropylcellulose (HPC) as a dry binder in roller compaction processing. The formula included acetaminophen (APAP), microcrystalline cellulose, fine-particle HPC, croscarmellose sodium, and magnesium stearate. The fine-particle HPC was incorporated into the formula at 4%, 6%, and 8% w/w levels. Three compaction pressures (30, 40, and 50 bars) were used for each formulation. The roller compaction equipment used in this study had a processing capacity of 40 to 80 kg/hr. A tablet compression profile was generated on a rotary tablet press, and compression forces used were 5, 10, 15, 20, and 25 kN. The significant criteria for tablet evaluation were capping, hardness, friability, ejection force, and drug dissolution. As the binder concentration of HPC increased, tablet capping decreased, and tablet friability improved. As the concentration of HPC increased, only slight differences were noted in tablet hardness. All the formulations pass the USP requirement of 80% APAP dissolved within 30 min. Using 8% HPC could eliminate the formula capping problem. The friability results were less than 1% at all compression forces. The minimum tablet ejection forces were found in the formulations prepared under 40 bars compaction pressure. The utility of fine-particle HPC as a roller compaction binder was established. The applicable binder concentrations and roller compaction pressures were found. Using HPC at these binder levels and operating parameters could overcome capping and friability problems and achieve the optimal tablet dosage forms.     

Investigating the Fundamental Effects of Binders on Pharmaceutical Tablet Performance

For solid dosage forms, a better understanding of the fundamental properties of the binders helps in developing better formulations and products. The objective of this study was to determine the effects of binder toughness and plastic flow on tablet hardness, friability, and capping. The characteristic of binder toughness was determined, and the correlation between the ejection force of the tablet and the toughness of the binder was established. Evaluation was conducted using acetaminophen tablets with different kinds of binders (i.e., hydroxypropylcellulose, methylcellulose [MC], povidone [PVP], starch, etc.). A rotary tablet press was used for tableting at three different speeds. The properties of binders and acetaminophen tablets were determined using a diametral compression test. The toughness was measured as the curve of the area under the load versus deflection. The microbehavior of these binders was also studied. The acetaminophen tablets with the binders were subjected to predetermined loads and then examined under a scanning electron microscope. The tablets that contained hydroxypropylcellulose as a binder showed the highest toughness and had the lowest ejection force. The ejection force of tablets decreased with increasing concentrations of hydroxypropylcellulose in the dosage forms. The tablets that contained other binders failed by capping and random cracking in the middle. These results show that hydroxypropylcellulose, a thermoplastic polymer, provides the best physical characteristics for the tablets. This effect could help in improving tablet manufacturing conditions (e.g., compression force and speed).