Study protocols multicenter studies

The treatment groups should be compared by use of the analyses that were outlined in the protocol. For multicenter studies, the information presented should give a clear picture of the results at each site. 

One of the most important means of quality control of a clinical study is managed by frequent and thorough monitoring. A monitor s aim is first to protect the agenda of the sponsor/CRO who employs him/her. Monitors (often referred to as CRAs or Clinical Research Associates or Assistants in the pharmaceutical industry) must ensure maintenance of proper standards, compliance with the protocol, accurate and complete data capture and standardization across sites in a multicenter study. Basically, monitors will undertake the review noted in Table 12.8. 

Number of subjects to be studied and justification for sample size (this information should be in the protocol). The committee will be interested in how many subjects will be exposed to the risk of treatment. In a multicenter study, the local ethics committee/IRB should be informed of the number of subjects to be enrolled at each site and the total number of subjects to be enrolled in the study... 

Different centers often draw subjects from different types of patient populations. Also, different centers may utilize different procedures and medical practices that are not controlled by the study protocol. It is, therefore, reasonable to expect that the within-center variability is smaller than the overall variability. In a multicenter trial, the center often serves as a stratification variable, thereby reducing the variability and increasing the efficiency of the trial design. In order to take advantage of this aspect of the multicenter trial, the number of subjects per center cannot be too small so that the estimate of the intra-center variability is stable. A rule-of-thumb is that the number of subjects per treatment group within each center will be at least 5. 

As already discussed, new protocols for absolute quantification of mlz signals is among the most recent and important efforts in MSI. This will not only help in controlling the reproducibility of experiments, but more importantly, it will enable the absolute comparability between experiments to be assessed. When achieved, this will pave the way for clinical multicenter studies. 

Decisions about treatment are influenced by guidelines - commonly accepted or not - which are discussed below. Clinically oriented decisions, individually influenced by our knowledge about the family situation, the estimated compliance with medical treatment, and the adherence to follow-up investigations, seem to be of equal importance. Aside from patients being involved in multicenter studies with strict protocols, treatment of many children with VUR is based on individual experience, local... 

Case report form completion All study personnel who will be entering data into the CRF should be present for review. The CRF contains all data required by the protocol. Instructions are provided for correct entry of data into the CRF, and the sites are reminded that all areas of the CRF are to be completed accurately. No data fields should be left blank. The abbreviations UNK, N/A, or ND are to be used when information is not known and whiteout or obliteration of data is not permissible. If a correction is needed in the CRF, study personnel are to strike through the incorrect entry with a single line, record the correct entry, and initial and date the correction. In a multicenter trial with many centers, instructions or guidelines for correct data entry on each page can be included in the CRF. This allows for uniform entry of data across many centers. 

Solez K, Vincent F, Filo RS. Histopathologic findings from 2-year protocol biopsies from a U.S. multicenter kidney transplant trial comparing tacrolimus versus cyclosporine a report of the FK506 Kidney Transplant Study Group. Transplantation 1998 66 1736-1740. 

The study was a nonrandomized, multicenter, open-label trial using five different dose regimens with inclusion and exclusion criteria as shown in Table 1 (6). The primary requirement consisted of subfoveal CNV with some classic component. Standardized protocol refractions, visual acuity determinations, complete ophthalmic examinations, color fundus photography, and fluorescein angiography were performed at baseline (between one and seven days prior to the day of treatment), and... 

Methoxsalen is supplied in soft gelatin capsules (Oxsoralen-Ultra) and hard gelatin capsules (8-MOP). The dose is 0.4 mg/kg for the soft capsule and 0.6 mg/kg for the hard capsule taken 1.5 to 2 hours before UVA exposure. A lotion containing 1% methoxsalen (Oxsoralen) also is available for topical application. It can be diluted for use in bath water to minimize systemic absorption. The risk of phototoxicity is increased with topical PUVA therapy. In U.S. and European multicenter cooperative studies of PUVA for the treatment of psoriasis, initial clearance rates approaching 90% were achieved. Relapse occurs within 6 months of cessation of treatment in many patients, which has prompted efforts to design maintenance protocols. 

To learn more about a Multicenter Phase III Randomized Study of American Ginseng (Panax quinquefolius) in Patients With Cancer-Related Fatigue, contact protocol co-chair Charles Loprinzi via e-mail at do prinzi mayo.edu. 

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