野田 和敬

PURPOSE: We hypothesized that even with appropriate clinical information, abnormal CT findings can still be missed if correct diagnostic predictions are not made. MATERIALS AND METHODS: Of 388 total students (97 5th-year medical students × 4), students who detected abnormalities without clinical information were eliminated. The remaining students (hereafter, subjects) obtained clinical information, made diagnostic predictions, and reevaluated images. The proportion of failures in detecting abnormalities was compared between the correct prediction group and the incorrect prediction group. In the correct prediction group, the relationship between failures of detection and the ranking of the correct diagnosis was also examined. RESULTS: A total of 341 subjects were assessed. The proportion of subjects who failed to detect abnormalities in the correct prediction group (47.7 %, 93/195) was significantly lower (P < 0.001) than in the incorrect prediction group (85.6 %, 125/146). In the correct prediction group, the proportion of subjects who failed to detect abnormalities was significantly lower (P = 0.004) when the correct diagnosis was ranked first (38.5 %, 42/109) compared with lower rankings (59.3 %, 51/86). CONCLUSION: Making appropriate diagnostic predictions and estimating the possibility of them based on clinical information is important to avoid missing abnormal CT findings.

PURPOSE: To compare the diagnostic accuracy of diseases predicted from patient responses to a simple questionnaire completed prior to examination by doctors with different levels of ambulatory training in general medicine. PARTICIPANTS AND METHODS: Before patient examination, five trained physicians, four short-term-trained residents, and four untrained residents examined patient responses to a simple questionnaire and then indicated, in rank order according to their subjective confidence level, the diseases they predicted. Final diagnosis was subsequently determined from hospital records by mentor physicians 3 months after the first patient visit. Predicted diseases and final diagnoses were codified using the International Classification of Diseases version 10. A "correct" diagnosis was one where the predicted disease matched the final diagnosis code. RESULTS: A total of 148 patient questionnaires were evaluated. The Herfindahl index was 0.024, indicating a high degree of diversity in final diagnoses. The proportion of correct diagnoses was high in the trained group (96 of 148, 65%; residual analysis, 4.4) and low in the untrained group (56 of 148, 38%; residual analysis, -3.6) (χ (2)=22.27, P<0.001). In cases of correct diagnosis, the cumulative number of correct diagnoses showed almost no improvement, even when doctors in the three groups predicted ≥4 diseases. CONCLUSION: Doctors who completed ambulatory training in general medicine while treating a diverse range of diseases accurately predicted diagnosis in 65% of cases from limited written information provided by a simple patient questionnaire, which proved useful for diagnosis. The study also suggests that up to three differential diagnoses are appropriate for diagnostic prediction, while ≥4 differential diagnoses barely improved the diagnostic accuracy, regardless of doctors' competence in general medicine. If doctors can become able to predict the final diagnosis from limited information, the correct diagnostic outcome may improve and save further consultation hours.

Pain is physiologically classified as nociceptive pain, neuropathic pain, and psychogenic pain. Nociceptive pain is further divided into visceral pain, somatic pain, and referred pain. Visceral pain is dull, and it is difficult to locate the origin of such pain. Somatic pain is sharp, severe, and well localized. On receiving visceral input for pain, it affects somatic nerve inputting to the same spinal segments, then referred pain is felt in the skin and muscles supplied by it. Referred pain is felt in an area that is located at a distance from its cause. History taking is the most important factor for determining the cause of pain. Generally, all the necessary information regarding pain can be acquired if pain-related history is obtained using the "OPQRST" mnemonic, that is, onset, provocation/palliative factor, quality, region/radiation/related symptoms, severity, and time characteristics.

Background: Taking a good history is important for the diagnosis of abdominal pain. We investigated questionnaire items that were significantly correlated with causes of abdominal pain requiring hospitalization. We also studied the combination of responses that could exclude severe disease.<br>Method: Between February 2006 and December 2007, 296 of 317 patients with abdominal pain who attended our Outpatient Department completed a questionnaire for their abdominal pain. They included 32 patients requiring hospitalization (severe group) and 264 other patients (mild group). The percentage of positive responses to each questionnaire item was compared between the two groups, and those showing a significant difference were employed for logistic regression analysis.<br>Results: The following 4 responses were selected: "It is less than 7 days since the onset of pain" (odds ratio [OR], 2.8; 95% confidence interval [95% CI], 1.2-6.4); "The pain is exacerbated by walking" (OR, 2.8; 95% CI, 1.3-6.2); "The pain is accompanied by weight loss" (OR, 3.8; 95% CI, 1.5-9.8); and "The pain wakes me at night" (OR, 2.3; 95% CI, 1.1-5.2). If a patient had none of these responses, the predictive value was 0.03 for severe disease.<br>Conclusions: Our findings suggested that pain reported within 7 days, exacerbation by walking, nocturnal awakening, and associated weight loss are features of abdominal pain that predict severe disease. Conversely, severe disease can be almost completely excluded in patients negative for all 4 features.

RATIONALE, AIMS AND OBJECTIVES: To investigate the subsequent behaviour of doctor-shopping patients (defined as those attending multiple hospitals for the same complaint) who consulted our department and factors related to cessation of doctor shopping. METHODS: Patients who presented without referral to the Department of General Medicine at Chiba University Hospital in Japan (our department) completed a questionnaire at their first visit. A follow-up questionnaire was also sent to them in order to assess doctor shopping after 3 months. Then items in the questionnaires were investigated for significant differences between patients who continued or stopped doctor shopping. Logistic regression analysis was performed with items showing a significant difference between patients who stopped doctor shopping and those who continued it, in order to identify independent determinants of the cessation of shopping. RESULTS: A total of 978 patients who presented spontaneously to our department consented to this study, and 929 patients (95.0%) completed questionnaires correctly. Among them, 203 patients (21.9%) were identified as doctor shoppers. The follow-up survey was completed correctly by 138 patients (68.0%). Among them, 25 patients (18.1%) were found to have continued doctor shopping, which was a significantly lower rate than before (P < 0.001). Logistic regression analysis selected the following factors as independent determinants of the cessation of doctor shopping: 'confirmation of the diagnosis' (odds ratio: 8.12, 95% confidence interval: 1.46-45.26), and 'satisfaction with consultation' (odds ratio: 2.07, 95% confidence interval: 1.42-3.01). CONCLUSION: Doctor shopping decreased significantly after patients consulted our department, with 'confirmation of the diagnosis' and 'satisfaction with consultation' being identified as contributing factors.

OBJECTIVE: Carnett's test is a simple clinical test in which abdominal tenderness is evaluated while the patient tenses the abdominal muscles. It is useful for differentiating abdominal wall pain from intra-abdominal pain. However, no study has reported its association with psychogenic abdominal pain. We evaluated its diagnostic usefulness in psychogenic abdominal pain. METHODS: Two physicians performed Carnett's test on each patient, but only one received the medical history. The other physician only conducted the test. Based on the final diagnosis, patients were categorized into 3 groups: psychogenic pain, abdominal wall pain, or intra-abdominal pain. Each group was analyzed in association with the results of Carnett's test conducted by the blinded physician. PATIENTS: A total of 130 outpatients with the chief complaint of abdominal pain who had abdominal tenderness. RESULTS: There were 22 patients with psychogenic abdominal pain, 19 with abdominal wall pain and 62 with intra-abdominal pain. In patients with psychogenic pain or abdominal wall pain, Carnett's test was usually positive, whereas the test was usually negative in patients with intra-abdominal pain (p<0.001, respectively). The positive likelihood ratio of Carnett's test for psychogenic abdominal pain was 2.91 (95% confidence interval [CI], 2.71-3.13), while the negative likelihood ratio was 0.19 (95% CI, 0.11-0.34). The corresponding values for abdominal wall pain were 2.62 (95% CI, 2.45-2.81) and 0.23 (95% CI, 0.13-0.41), respectively. CONCLUSION: Carnett's test may be useful for ruling in and ruling out psychogenic abdominal pain in addition to distinguishing between abdominal wall pain and intra-abdominal pain.

OBJECTIVE: Patient medical history is important for making a diagnosis of causes of dizziness, but there have been no studies on the diagnostic value of individual items in the history. This study was performed to identify and validate useful questions for suspecting a diagnosis of benign paroxysmal positional vertigo (BPPV). METHODS: Construction and validation of a disease prediction model was performed at the outpatient clinic in the Department of General Medicine of Chiba University Hospital. Patients with dizziness were enrolled (145 patients for construction of the disease prediction model and 61 patients for its validation). This study targeted BPPV of the posterior semicircular canals only with a positive Dix-Hallpike test (DHT + BPPV) to avoid diagnostic ambiguity. Binomial logistic regression analysis was performed to identify the items that were useful for diagnosis or exclusion of DHT + BPPV. RESULTS: Twelve patients from the derivation set and six patients from the validation set had DHT + BPPV. Binomial logistic regression analysis selected a "duration of dizziness ≤15 seconds" and "onset when turning over in bed" as independent predictors of DHT + BPPV with an odds ratio (95% confidence interval) of 4.36 (1.18-16.19) and 10.17 (2.49-41.63), respectively. Affirmative answers to both questions yielded a likelihood ratio of 6.81 (5.11-9.10) for diagnosis of DHT + BPPV, while negative answers to both had a likelihood ratio of 0.19 (0.08-0.47). CONCLUSION: A "duration of dizziness ≤15 seconds" and "onset when turning over in bed" were the two most important questions among various historical features of BPPV.

We report a 38-year-old mestizo man with the sudden onset of left upper abdominal pain while climbing Mt. Fuji, which is the highest mountain in Japan. Enhanced computed tomography showed splenic infarction. Although his peripheral blood smear was normal, a hemoglobin S level of 40% established the diagnosis of sickle cell trait (SCT). This trait is common worldwide, but is not well recognized by doctors in Japan because no Japanese patients with SCT have been reported. However, in Japan it is important to consider SCT when assessing foreign patients with splenic infarction.