The Delphi list: a criteria list for quality assessment of randomized clinical trials for conducting systematic reviews developed by Delphi consensus

Most systematic reviews rely substantially on the assessment of the methodological quality of the individual trials. The aim of this study was to obtain consensus among experts about a set of generic core items for quality assessment of randomized clinical trials (RCTs). The invited participants were experts in the field of quality assessment of RCTs. The initial item pool contained all items from existing criteria lists. Subsequently, we reduced the number of items by using the Delphi consensus technique. Each Delphi round comprised a questionnaire, an analysis, and a feedback report. The feedback report included staff team decisions made on the basis of the analysis and their justification. A total of 33 international experts agreed to participate, of whom 21 completed all questionnaires. The initial item pool of 206 items was reduced to 9 items in three Delphi rounds. The final criteria list (the Delphi list) was satisfactory to all participants. It is a starting point on the way to a minimum reference standard for RCTs on many different research topics. This list is not intended to replace, but rather to be used alongside, existing criteria lists.

Balneotherapy and quality assessment: interobserver reliability of the Maastricht criteria list and the need for blinded quality assessment

This study investigates aspects of the reliability of the Maastricht criteria list for quality assessment in systematic reviews, and whether blinded reviewing is necessary to prevent review bias. We used the data set of 12 articles from a systematic review concerning the efficacy of balneotherapy in patients with arthritis. Twenty reviewers participated of which two reviewers, who have been involved in developing the Maastricht criteria list, acted as reference standard. Half of all assessments were performed blindly. A high level of agreement was found between the reviewers and a high level of correlation with the reference standard. The quality scores between the blinded and unblinded assessment did not differ much. Based on the results we conclude that the Maastricht criteria list is a reliable instrument in quality assessment of clinical trials. Within the limits of this study we found no evidence that blinding is necessary to prevent review bias.

Taking baths: the efficacy of balneotherapy in patients with arthritis. A systematic review

OBJECTIVE

To review English, French, German, and Dutch language studies of the effectiveness of balneotherapy. Balneotherapy (hydrotherapy or spa therapy) is one of the oldest forms of therapy for patients with arthritis. One of the aims of balneotherapy is to relieve pain.

METHODS

We performed a systematic review that included randomized and nonrandomized studies. Quality scores of the studies were determined using a criteria list.

RESULTS

Most studies report positive findings, but all studies showed methodological flaws. A quality of life measurement was never reported as an outcome measure. None of the randomized clinical trials included intention-to-treat analysis or comparison of effects between groups.

CONCLUSION

Because of the methodological flaws a conclusion about the efficacy of balneotherapy cannot be provided from studies we reviewed. We conclude that most flaws found could be avoidable in future research.

Whiplash: assessing the validity of diagnostic tests in a cervical sensory disturbance

OBJECTIVE

To determine the ability of two diagnostic tests that examine sensory disturbance in whiplash patients to discriminate between 'extreme' groups.

BACKGROUND

The neuromuscular theories have been accepted as explanations of the symptoms after a whiplash injury. Dutch manual therapists often use the diagnostic tests under study to diagnose and treat sensory disturbances after such an injury. The validity of a test needs to be assessed before its efficacy as a treatment in whiplash patients can be tested. The aim of this study was to validate two diagnostic tests and to initiate further research on the efficacy of a treatment of a sensory disturbance in whiplash patients.

METHOD

Twelve subjects with chronic symptoms (> 3 months) after a whiplash injury (patient group) and 18 subjects without any head or neck problems (control group) were studied. The tests under study were the extension test and the coordination test. All researchers were blind to the characteristics of the subjects.

RESULTS

The extension test and the coordination test were able to discriminate adequately between subjects with symptoms after a whiplash injury (patients) and subjects without any head or neck complaints (control subjects). Patients clearly show a smaller degree of extension compared with the control subjects and an increase of extension movement with external fixation. The sensitivity as well as the specificity of the coordination test were good (both > .80).

CONCLUSION

These diagnostic tests seemed to be valid instruments for discriminating between whiplash patients with symptoms and healthy people.

Colocalization of basal and luminal cell-type cytokeratins in human prostate cancer

In the epithelium of secretory acini of the prostate two different cell types can be discriminated on the basis of localization, morphology, and degree of differentiation, the luminal and basal cells. The possibility of a developmental relationship between basal and luminal cells has been a subject of interest in several studies. According to the stem cell model at least three cell types, i.e., stem, amplifying, and transit cells, can be discriminated in the epithelium of prostate secretory acini. We previously reported that in the process of degeneration and regeneration in normal rat prostate a population of cells could be identified as candidates for the amplifying cells. These cells showed a keratin expression profile intermediate between those of basal and luminal cells. We now show, by using keratin antibodies, that also in normal human prostate at least three subpopulations of cells can be identified, one of them putatively representing amplifying cells as defined in the stem cell model. Furthermore, these antibodies were used to obtain a better insight into the different cell types involved in the etiology and progression of prostatic carcinoma. Both primary and hormone-independent prostatic tumors were investigated. Our results indicated that the candidate stem cell population was absent in prostatic carcinoma. Unlike earlier reports on the unique presence of cells with luminal characteristics in prostatic carcinoma, we identified also a population of cells coexpressing basal and luminal cell-type cytokeratins in primary and hormone-independent prostatic carcinoma. Since amplifying cells are defined in the stem cell model as precursors of transit (luminal) cells in the hierarchical pathway of prostatic epithelium differentiation, we postulate that on the basis of the keratin expression profile this subpopulation is most likely the target for neoplastic transformation.

Intermediate filament expression and the progression of prostatic cancer as studied in the Dunning R-3327 rat prostatic carcinoma system

To evaluate if there is any consistent relationship between the expression of intermediate filament proteins (IFP), particularly keratins, and the degree of malignancy of prostatic cancer cells, a series of nine Dunning rat prostatic cancer sublines that span the entire spectrum of progression of prostatic cancer were studied immunocytochemically by the use of a variety of antibodies specific for keratins, vimentin, or desmin. For the keratin studies, monoclonal antibodies with either a general reactivity to several keratins or highly specific for either luminal or basal epithelial cells of the normal rat prostate were used. By use of an antibody specific for luminal cell keratin 18, the luminal tumor cells of the well-differentiated, slow-growing H and HI-S sublines were positively stained. In most of the sublines with a more advanced state of progression (i.e., the moderately differentiated, moderately fast growing HI-M; the poorly differentiated, faster growing HI-F; and the anaplastic, very fast growing AT-1, AT-2, and MAT-Lu tumors), however, no expression of keratin specific for luminal cells was detected. In addition, several of the most advanced sublines (i.e., AT-1, AT-2, and MAT-Lu) were negative using any of the keratin antibodies. In contrast, several of the other sublines with the most advanced degree of progression (i.e., the anaplastic, very fast growing MAT-LyLu tumor derived from the AT-1 subline; and the anaplastic, very fast growing AT-3 tumor, derived from the HI-F subline), however, were positively stained with the keratin antibody specific for the luminal cells. By use of the keratin antibody specific for the basal cells of the normal rat prostate, the basal tumor cells of the well-differentiated slow-growing H and HI-S tumor were positively stained. This positive staining for basal cell keratin was also found in the HI-M and HI-F tumors, while the AT-1, AT-2, MAT-Lu, MAT-LyLu, and AT-3 were negative with this antibody. Thus, a loss in staining for basal cell keratin was consistently associated with the most advanced state of tumor progression. Vimentin-positive staining was demonstrated either alone or with keratin-positive staining in part of the epithelial cancer cells of all the sublines. An increase in the positive staining for vimentin was consistently associated with a more advanced state of tumor progression. Desmin-positive staining was found only in smooth cells present within the various tumor sublines.(ABSTRACT TRUNCATED AT 400 WORDS)

Differential expression of keratins in the basal and luminal compartments of rat prostatic epithelium during degeneration and regeneration

The role of the different epithelial compartments during degeneration and regeneration of the rat prostate is examined on basis of intermediate filament protein (IFP) expression pattern. With the monoclonal antibodies RCK 103 and RGE 53, directed against specific keratins, it was possible to differentiate between the basal (RCK 103+) and luminal (RGE 53+) cells of the prostatic epithelium. After testosterone deprivation, by orchiectomy, an extensive and rapid cell loss was observed which appeared to affect mainly the luminal cells. In the process of prostate regeneration, induced by testosterone administration, using silastic implants, the luminal compartment rapidly regained its normal thickness. A heterogeneous population of morphologically luminal cells was observed showing keratin expression patterns intermediate between basal and luminal cells. These findings support the idea of a relationship between basal and luminal cells as being members of the same lineage of differentiation.

Antibodies against distinct nuclear matrix proteins are characteristic for mixed connective tissue disease

Specific nuclear proteins, separated according to their molecular weight (mol. wt) by polyacrylamide gel electrophoresis (PAGE) and subsequently transferred to nitrocellulose sheets, are able to bind antibodies in sera from patients suffering from different types of connective tissue diseases. Antibodies against a characteristic set of nuclear protein antigens are found in sera from patients with mixed connective tissue disease (MCTD). Screening of 21 MCTD sera revealed a typical immunoblot pattern with major protein antigens of mol. wt 70,000 (20/21) (not identical with the Scl-70 antigen characteristic for scleroderma), mol. wt 31,000 (17/21), two proteins around mol. wt 23,000 (15/21) and two around mol. wt 19,000 (10/21). The 70,000, 23,000 and 19,000 antigens appeared to be rather insoluble nuclear proteins (i.e. components of the nuclear matrix). On behalf of their structural character they were present in nuclei from several types of cells but only in low amounts detectable in salt extracts of thymus acetone powder. The presence of antibodies directed against the mol. wt 70,000 antigen correlated strongly with the diagnosis of MCTD. This 70,000 antigen is not identical with the RNP antigen, a soluble ribonuclease sensitive ribonucleoprotein, since antibodies against nuclear RNP can be separated from anti-nuclear matrix antibodies by affinity chromatography using immobilized thymus salt extract. The distinct character of soluble nuclear RNP and structural nuclear matrix antigens is further supported by the fact that from 14 other anti-RNP sera obtained from patients with systemic lupus erythematosus (SLE), only three contained antibodies against the mol. wt 70,000 protein. Since the immunoblot pattern obtained with MCTD sera mostly was clearly distinguishable from the patterns obtained with sera from patients with related connective tissue diseases our results suggest that the immunoblotting technique might be useful as a diagnostic tool and support the concept of MCTD as a distinct entity.