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We conducted a community-based pilot study to train Hispanic cancer survivors as promotoras (lay health educators) to encourage their social contacts to obtain breast and cervical cancer screening. Promotoras were recruited from a private oncologist's practice at a Minority-Based Community Clinical Oncology Program (MBCCOP). Five Hispanic women were trained to serve as promotoras by attending a 12-week course. They shared cancer screening information with family and social contacts and encouraged them to obtain Papanicolaou smears and/or mammograms. Study endpoints included the number of women recruited and trained to serve as promotoras, the number of contacts made per promotora, and the number of contacts who were screened; data were based on contact logs maintained for 1 year. Screening examinations were documented by a postcard returned by the contact or by review of community health clinic records. Five promotoras contacted 141 (range = 24-49 per promotora) women to share cancer screening information. Fifty Hispanic women obtained screening after contact with a promotora. Twenty-nine underwent mammography (ages 25-58) and 43 received a Papanicolaou smear (ages 23-62). Hispanic female cancer survivors can be trained as promotoras. Screening information conveyed by a promotora can successfully prompt Hispanic women to obtain mammography and Papanicolaou smears.

The Prostate Cancer Prevention Trial is an intergroup effort in the USA managed by the Southwest Oncology Group (SWOG) in collaboration with the Eastern Cooperative Oncology Group (ECOG) and the Cancer and Leukemia Group B (CALGB). This 10-year study began approximately 5 years ago and will achieve its primary endpoint in October 2004. At the start of the study, 18,882 men, aged over 55 years, and with normal digital rectal examination (DRE) and serum prostate-specific antigen (PSA) levels of ≤3.0 ng/ml were randomized to take finasteride (5 mg/day) or placebo (1 tablet/day). DRE and PSA have been determined yearly (PSA in a central laboratory). When DRE is abnormal or PSA rises to >4.0 ng/ml, a biopsy is recommended. Because of the effect finasteride has on PSA, the PSA value has been indexed to equalize the number of biopsies in both arms. At 7 years all survivors will undergo a sextant biopsy to determine the period prevalence of prostate cancer. The critical assumptions are: (1) finasteride-induced PSA changes result in a simple downward shift; (2) the assessment of adherence is sensitive enough to detect nonadherence affecting PSA level interpretation: (3) factors affecting biopsy loss will be equal in both arms; (4) finasteride does not affect the sensitivity or specificity of DRE on transrectal ultrasound nor the sensitivity of biopsy; (5) bias resulting from transurethral resection of the prostate in benign prostate hyperplasia cases will be negligible.

The PCPT is a chemoprevention trial of finasteride with a primary endpoint of biopsy-proven presence or absence of prostate cancer. A total of 18,000 healthy men, aged 55 years and older, will be randomized. Half will receive finasteride (5 mg/day) and half will receive placebo (one matching tablet per day) for 7 years. The trial is designed to have 92% power to detect a 25% reduction in period prevalence of biopsy-proven disease using a two-sided test with alpha = 0.05. The trial is complicated by the known impact of finasteride on the major screening test for prostate cancer, prostate specific antigen (PSA). This paper describes the PCPT design with reference to alternatives that were considered. The chosen design depends on five critical assumptions that must be monitored closely throughout the 9-year trial.

Inter- and intralaboratory reproducibility of susceptibility testing requires stable control strains. The Food and Drug Administration diffusion procedure recommends the Seattle strains of Staphylococcus aureus (ATCC 25923) and Escherichia coli (ATCC 25922) for this purpose. It was of interest to determine the present reproducibility of control cultures maintained in various laboratories over several years. Fifteen cultures each of S. aureus and E. coli were obtained from laboratories in different parts of the country. Their performance was compared with strains directly derived from ATCC. Diffusion susceptibility tests using a modified overlay technique were made with four replicates. Seven of the eight statistically significant differences in responses of the staphylococci were to penicillin, methicillin, or cephalothin. One culture was a penicillinase producer with a zone 15 mm less than the standard strain. Eleven of the 15 cultures showed no significant deviations or differences greater than 2 mm from the results with the strain derived directly from ATCC. All except the penicillinase producer were of identical phage type. Among 150 organism-antibiotic combinations tested with E. coli , all but one reading were within 2 mm of the standard. Four of the six statistically significant differences were in a culture from one laboratory. The stability of the cultures appears to have been influenced by the method of storage. Cultures that were kept frozen during extended storage were remarkably stable. Significant differences were found in cultures from four of five laboratories that maintained cultures in refrigerators or at ambient temperature.

Records of hospital inpatients were abstracted for 5,000 newly diagnosed cancer patients admitted in 1982-83 to 17 Comprehensive Cancer Centers and 17 Community Hospital Oncology Programs. Generally available data items (silent record rate less than 5 per cent for the typical institution) included: age, race, sex, dates of hospitalization, zip code of residence, pathological stage, dates of biopsy and surgery, numbers of nodes examined and positive, certain diagnostic procedures, and some radiotherapy descriptors. For other data items, there was enormous variability in completeness and high institution-to-institution variation. Record completeness did not differ consistently between comprehensive and community cancer centers. We conclude that the hospital patient record is useful for tracking the frequency of surgical and related events. However, studies of diagnostic and therapeutic procedures should not rely solely on the hospital medical record due to the high rates of silent records.

A random sampling method of measuring the completeness of registration of cancer patients was tested at a university referral hospital. The target population consisted of all inpatients and nonprivate outpatients with in situ or invasive malignancies. The medical records of a random sample of all hospital records active in the last five years were reviewed to determine their reportability and inclusion in the tumor registry (Method A). Traditional casefinding assessment methods were also employed by conducting a complete review of four commonly used hospital sources for a short time period (Method B). The primary purpose of the study was methodologic; namely, to test the feasibility of Method A and to characterize it relative to the more traditional Method B. The estimated missed case rates using Methods A and B (3% and 5%, respectively) are not directly comparable because not all outpatient information is recorded in the medical record. It is concluded that as a means of completeness assessment, Method A can be feasible, cost effective, and useful in other institutions provided certain conditions are met: (1) an appropriate random sample of the target population can be obtained; (2) all relevant information is available in a unit medical record; (3) the reviewer is fully aware of the reportability criteria.

The National Wilms' Tumor Study, initiated in 1969, tested competing treatment strategems for patients with tumors ranging from Group (Gp) I (tumors confined to the kidney and totally removed) to Gp IV (remote metastases present at diagnosis). Three hundred and fifty-nine of 606 registered patients were randomized in the trial. Gp I patients under 2 years of age fared well whether postoperative radiation therapy (RT) was or was not added to 15 months' maintenance actinomycin D (AMD). Their prognosis was better than that for older cohorts similarly treated, in whom the difference in relapse rates between treatment groups were suggestive of an RT effect. Combined AMD and vincristine (VCR) gave better results than either agent alone in patients with more advanced tumors (Gps II and III) still confined to the abdomen, all of whom received postoperative RT as well. Preoperative VCR given Gp IV patients in addition to postoperative RT, AMD, and VCR did not improve results. The frequency of mesoblastic nephroma (1%), of bilateral tumors (5%), and of incorrect preoperative diagnosis of Wilms' tumor (5%), the toxicities of the various regimens, and other ancillary data are presented and discussed.

The analysis of binomial data in the presence of 'change performance' or a natural response is discussed. The response and predictors are assumed to be related through a probit or logit link function. The baseline rate may be known a priori as in a forced choice experiment or have to be estimated as in biological studies. Both situations are conveniently analyzed in GLIM. When the baseline is estimated either the EM algorithm or a composite link function may be used.

Long-term survival rates were correlated with selected clinical features in 479 patients with embryonal carcinoma of the testis and 33 patients with endodermal sinus tumor (infantile embryonal carcinoma, yolk sac tumor). In the period 1977 to 1982 embryonal carcinoma accounted for 26.8% of newly diagnosed germ cell tumors and 43% of nonseminomatous germ cell tumors entered in the Centralized Cancer Patient Data System. Among patients with embryonal carcinoma, over 80% were diagnosed in the 15-to-34 year age group. Seventy-four percent of the patients had metastatic disease at the time of diagnosis, and 50% of these had distant metastases, attesting to the aggressiveness of embryonal carcinoma and its tendency to early hematogenous spread. Despite the highly malignant nature of the tumor, the overall 5-year survival rate with treatments used was an excellent, 88%. Survival was correlated with the extent of disease at the time of diagnosis; the 5-year actuarial survival rates for patients with localized, regional, and distant disease were 98%, 96%, and 74%, respectively. Endodermal sinus tumor was uncommon (1.8% of all testicular germ cell tumors), occurred predominantly in the younger age group (0-24 years), and in 50% of the cases was localized to the testis. The survival rate for the 33 patients with this form of tumor was slightly worse than for the "adult form" of embryonal carcinoma. The authors conclude that survival of patients with embryonal carcinoma has greatly improved over the last decade as a result of improved methods for early detection of metastatic deposits and the effectiveness of newer chemotherapies in the treatment of disseminated disease.

Two hundred forty rats were given renal infections with a methicillin-resistant strain of Staphylococcus aureus. Animals were treated intraperitoneally once daily for 10 days with vancomycin, cephalothin, or kanamycin, or with cephalothin and kanamycin combined, or with methicillin or saline. Total daily doses were equal to usual doses in humans on the basis of mg per kg of body weight. Under the conditions of this experiment, vancomycin and the combination of cephalothin and kanamycin were more effective than the other drugs; cephalothin alone and kanamycin alone were indistinguishable from each other, but were clearly more effective than methicillin or saline; methicillin was not more effective than saline.

Vitamin A, beta-carotene, and synthetic retinoids have attracted wide interest as premising chemopreventive agents, based on work in rodents and in cultured cells and organs, and low dietary intake or low serum levels of vitamin A or beta-carotene have been associated with high risk for lung cancer (1–4). Even if the data were stronger, observational epidemiological studies cannot establish whether or not changing the vitamin A status of specific individuals or groups of individuals would alter their subsequent cancer risk. The hypothesis that increasing retinoid intake in humans would reduce the risk of lung cancer must be tested in humans. For both practical and ethical reasons, such studies should be undertaken initially among those at highest risk.

We studied the process of care received by 1,680 female breast cancer patients treated in 17 community hospitals. The probability of receiving various diagnostic, consultation, therapy, or rehabilitation services was almost always significantly associated with patient age for one or more disease stages. Most often there was a linear trend for older patients to receive fewer services (e.g., biopsies prior to definitive treatment, number of lymph nodes examined, chemotherapy, radiation therapy) but other age patterns also were found. Age was not significantly associated with clinical staging or estrogen receptors.

One hundred and twelve well-studied patients with a prior diagnosis of juvenile rheumatoid arthritis were differentiated into seven clinically distinct subgroups, including a group in whom recognizable ankylosing spondylitis had developed by time of follow-up. An apparent increased prevalence of HLA-B27 in the entire series (26%) was clearly related to its increased prevalence in only two subgroups: patients whose disease had progressed to overt ankylosing spondylitis (five of five patients) and boys with pauciarticular arthritis whose disease would be consistent with early ankylosing spondylitis (11 of 18 patients). There were no significant associations of B27 with systemic onset JRA, polyarticular JRA, pauciarticular JRA in girls, or JRA with chronic iridocyclitis. The only other significant alterations found were increased prevalences of HLA-A2 and HLA-BW15 in patients with polyarticular disease without identifiable rheumatoid factor. This study emphasizes that the clinical disorders included under the category of juvenile rheumatoid arthritis represent more than a single disease and that this heterogeneity must be considered in interpreting studies such as those of histocompatibility typing.

The evolution of the Centralized Cancer Patient Data System, a cooperative venture of the 21 comprehensive cancer centers in the United States, and its structure at the end of 3 years of data collection are described. Functions of the data system are detailed in terms of input and output. It is concluded that the short-run objective of establishing a data system to provide high-quality patient data that ae 21 comprehensive cancer centers in the United States, and its structure at the end of 3 years of data collection are described. Functions of the data system are detailed in terms of input and output. It is concluded that the short-run objective of establishing a data system to provide high-quality patient data that ae 21 comprehensive cancer centers in the United States, and its structure at the end of 3 years of data collection are described. Functions of the data system are detailed in terms of input and output. It is concluded that the short-run objective of establishing a data system to provide high-quality patient data that are comparable among cancer centers has been largely accomplished. Moreover, the very process of setting up the national data system has benefited the participating centers by upgrading their individual cancer registries. For the future, the goal is to realize the research potential of this new cooperative data collection mechanism, as well as the accumulating data themselves. Progress toward the long-term goal is just beginning.

In this presentation, issues that influenced the development of policies for inclusion of quality of life end points in certain Southwest Oncology Group clinical trials are reviewed. The key policies recommended by us and adopted by the Cancer Control Research Committee of the Southwest Oncology Group are as follows: (a) Begin assessment of quality of life in specific types of phase III protocols. (b) Always measure physical functioning, emotional functioning, symptoms (general and protocol specific), and global quality of life separately. (c) Include measures of social functioning and additional protocol-specific measures if resources permit. (d) Use patient-based questionnaires with psychometric properties that have been documented in published studies. In this review, we also recommend specific questionnaires. Our recommendations may prove useful for other cancer clinical trials groups and for multi-institution trials of treatment for chronic diseases.

The accuracy of data coded from the medical records of 985 patients from 22 major U.S. cancer centers was checked by recoding during 1978-81. The 29 items covered demographics, diagnosis, and therapy. Original codes were compared to recodes, and disagreements were classified as major or minor. The highest rate of major disagreements, 23%, was for stage of disease, followed by 10% for histology and 7% for site. Major disagreement rates for most other items were under 7%. Only 3% of a large sample of major disagreements involved justifiable differences in interpretation; the others were due to errors in the use of records. Major disagreement rates varied by a factor of 10 across sites, 4 across centers, and 2 across stage of disease. For several items the code "unknown" was overused and led to disagreements. A new procedure is presented for analysis of disagreement rates. The results from this procedure can guide training effort to improve coding accuracy.

Pooling patient data from multi-institutional medical chart review occurs commonly in the study of cancer and other diseases. To determine the consistency of reporting among institutions, we presented a test set of 25 standardized medical charts to coders at 18 Comprehensive Cancer Centers and compared their resulting codes. This study measures the reproducibility of coding by different persons, but does not assess the accuracy of the underlying medical record. Among 34 data items, we found high disagreement rates in coding stage of disease (14 per cent) and date of diagnosis (8 per cent). Primary site, histologic type and other key items had good reproducibility (disagreement rates less than or equal to 5 per cent). A number of minor disagreements indicated that detailed distinctions could not be reliably coded from medical charts.

The Centralized Cancer Patient Data System is the system which the 21 comprehensive cancer centers in the U.S. have established in order to report and to analyze demographic, diagnostic, treatment and survival data on all new patients. We propose that this closely monitored standardized 36 item dataset can be used to profile the categories of initial treatment that are given to patients having all types and stages of cancer: the data may be displayed for all centers or used to compare the approaches used at different centers. Differences in the frequency with which surgery, radiation, chemotherapy, and no specific treatment are used for patients having any of three commonh histologic types of lung cancer serve to illustrate the method. Opportunities now exist to utilize this new resource to study trends in the use of treatment modalities and their relationship to survival, which in turn should enhance the accessibility of treatment information about all patients at cancer centers, rather than only those which are reported from selected treatment protocols. This approach may also be uniquely useful in obtaining treatment and survival information about patients with rare sites or types of cancer.

Lung cancer is a major health problem in the USA. It is estimated that in 1982, greater than 110,000 deaths were directly attributable to lung cancer.1 In addition to being the most common cause of cancer death in man (and in 1985, women also), lung cancer is unique in that the primary causative agent has been identified. Epidemiologic studies have clearly shown that cigarette smoking is a major etiologic factor in the development of pulmonary neoplasia.2,3,4 Although the public is well aware of this relationship, there has been little success in primary prevention. In general, anti-smoking campaigns are met with apathy and tobacco abuse continues. Because the primary prevention of lung cancer has not yet been possible, alternative methods of prevention are needed for those who are unable or unwilling to give up smoking. The availability of a “chemoprevention drug” for this population would be of significant public health interest.

In a previous publication, we described a Doppler ultrasound method for diagnosing venous disease of the lower extremities.1This technique is used to detect occlusion of deep veins due to thrombosis and incompetent valves associated with the postphlebitic syndrome. The preliminary results in 72 patients with confirmed diagnoses indicated that the ultrasound method was significantly more precise than clinical appraisal alone in the diagnosis of thrombotic occlusion of deep veins of the lower extremities.2We have expanded this series by adding 75 more patients in whom confirmation of Doppler ultrasound findings was obtained usually by venography and occasionally by operation or autopsy. As our experience has increased, we have simplified the examination for occlusion by deleting certain maneuvers which were found to be redundant. This has enabled us to evolve a more systematic and specific set of criteria for abnormality on the ultrasound examination. Furthermore, the additional clinical

Considerable controversy surrounds the question of whether cigarette smoking has the potential to increase the prevalence of small opacities on chest roentgenographs among asbestos-exposed workers. To compare the relative contribution of smoking with other predictors of the presence of roentgenographic small opacities, we examined 661 men enrolled in a double-blind, randomized trial designed to assess the efficacy of vitamin A and beta-carotene in the prevention of lung cancer among workers with heavy occupational asbestos exposure. Subjects in the study population had a mean latency of 35 yr from first asbestos exposure and a mean of 28 yr in their trade. The prevalence of roentgenographic abnormalities consistent with asbestos exposure was 26% for pleural abnormalities alone, 10% for parenchymal abnormalities alone, and 20% for pleural and parenchymal abnormalities together. We investigated occupation, age, latency from first asbestos exposure, and smoking status as predictors of roentgenographic small opacities. Smoking history, independent of latency, contributed to the prevalence and extent of small opacities, but its effect was less than that of latency. We conclude, that in the setting of heavy occupational exposure to asbestos, cigarette smoking confers added risk for the development of roentgenographic small opacities.

Lung cancer increases in incidence with increasing age and is the leading cause of cancer death in the United States. While mass screening for lung cancer is not indicated, selective screening of high-risk target groups may be beneficial. We tested the hypothesis that lung cancer is initially seen at a less advanced stage with increasing age using incidence cases (N = 22874) from the Centralized Cancer Patient Data System. The percent of lung cancer patients with local stage disease increased from 15.3% of those aged 54 years or younger, to 19.2% of those aged 55 to 64 years, to 21.9% of those aged 65 to 74 years, and to 25.4% of those aged 75 years or older. The percent with distant stage decreased from 48.7%, to 44.5%, to 40.3%, and to 36.7% for the same age groups, respectively. These age-stage trends persisted in subgroup analysis by sex, race, and histological subtype. Furthermore, analysis of 6332 patients who underwent surgical staging showed a greater likelihood of local stage disease with increasing age. Thus, compared with the young, the group aged 65 years or older is at a greater risk for lung cancer and has a higher proportion of lung cancer initially seen at local stage. The efficacy of selective screening for lung cancer in this target group warrants additional study. (JAMA1987;258:921-926)

To examine the influence of partial antibiotic therapy on laboratory findings in Haemophilus influenzae meningitis, 272 untreated cases and 202 partially treated, culture-positive cases from 1953 through 1971 were reviewed. There was no significant difference between the two groups with respect to several cerebrospinal fluid (CSF) values. Both the untreated and partially treated groups had a similar proportion of cases with negative Gram stain and CSF glucose level over 40 mg/100 ml or a predominance of CSF mononuclear cells. Eight patients had received ampicillin sodium, chloramphenicol, or tetracycline for two days or more. The CSF findings of these patients resembled those of the untreated group. The data support the conclusion that antibiotics In the usual outpatient dosages seldom interfere with the diagnosis of H influenzae meningitis.

Standard sample size calculations for n, the number of observations per group when comparing two independent proportions, P1 and P2, require the specification of four quantities: P1, one of the two proportions of interest; delta = P2 - P1, the smallest difference which it is important to detect; alpha, the significance level; and beta, the chance of failing to detect a difference as large as delta. In terms of these four quantities, the graphical aid is a series of charts showing isographs of sample size for selected values of n ranging from 35 to 500. The isographs, i.e. curves connecting points of equal sample size, are based on the asymptotic arc sine approximation and are plotted on the grid formed by P1 on the abscissa and delta on the ordinate. Eight separate charts are available for different choices of alpha and beta. These charts are especially useful in situations where the feasible sample size is roughly known, in which case the detectable difference, delta, can be read directly from the graph.

The increasing influence of multicenter clinical trials in medicine since World War II, and the contributions of statistical methods to the success of such trials, are uncontested. The burgeoning interest in the methodology of clinical trials has been followed by the establishment of formal mechanisms for exchange of ideas, such as the Annual Symposium on Coordinating Clinical Trials and the newly founded Society for Clinical Trials. Nevertheless, as recently as February 1978, Robert S. Gordon, Jr wrote the following words in an editorial (Gordon, 1978)

In a double-blind crossover study, carbamazepine and phenytoin were compared as single anticonvulsants in 47 patients with focal and major generalized seizures. Each drug provided superior seizure control in about half the patients, but significantly fewer patients had objective side effects while taking carbamazepine. Neuropsychologic testing showed improved performance in cognitive function and emotional status of patients while and carbamazepine. No hematotoxic complications arose, but vigilant follow-up is advised. Mean serum level of carbamazepine was 9.3 microng per milliliter with a suggested therapeutic range of 8 to 12 microng per milliliter reached by eventual doses of 16 to 20 mg per kilogram. Carbamazepine offers an independent choice of improved seizure control with a possibility of fewer side effects.

Concomitant information on a l)atient's condition often accompanies survival time information. This paper presents a method of estimating survival distributions when the survival times are asstumed to follow simple exponential distributions, with a different parameter for eacli patient. The parameter associated with each patient's distribution is functionially related to the concomitant variates. The parameters are estimated by the method of maximum likelihood. An illustration of the method using acute leukemia survival data is given.

This text deals mainly with statistical methods appropriate for large samples. Frequency distributions, tabulation, graphing, use of centering constants and measures of variation, and other descriptive methods are treated in the introductory chapters. Further topics include the binomial and the use of normal distribution in large sample approximate tests of significance for differences in sample means and proportions. Additional chapters deal with the t tests and vital statistics (including the use of the modified life table techniques in follow-up studies), and the final chapter presents a brief discussion of quantal bioassay and the Reed-Muench method. The book was written with medical students and practicing physicians in mind.