Digit preference and biased conclusions in cardiac arrest studies.

BACKGROUND: In cardiac arrest (CA), time is directly predictive of patients' prognosis. The increase in mortality resulting from delayed cardiopulmonary resuscitation has been quantified minute by minute. Times reported in CA management studies could reflect a timestamping bias referred to as "digit preference". This phenomenon leads to a preference for certain numerical values (such as 2, 5, or 10) over others (such as 13). Our objective was to investigate whether or not digit preference phenomenon could be observed in reported times of the day related to CA management, as noted in a national registry. METHODS: We analyzed data from the French National Electronic Registry of Cardiac Arrests. We analyzed twelve times-of-the-day corresponding to each of the main steps of CA management reported by the emergency physicians who managed the patients in prehospital settings. We postulated that if CA occurred at random times throughout the day, then we could expect to see events related to CA management occurring at a similar rate each minute of each hour of the day, at a fraction of 1/60. We compared the fraction of times reported as multiples of 15 (0, 15, 30, and 45 - on the hour, quarters, half hour) with the expected fraction of 4/60 (i.e. 4 × 1/60). MAIN RESULTS: A total of 47,211 times-of-the-day in relation to 6131 CA were analyzed. The most overrepresented numbers were: 0, with 3737 occurrences (8% vs 2% expected, p < 0.0001) and 30, with 2807 occurrences (6% vs 2% expected, p < 0.0001). Times-of-the-day as multiples of 15 were overrepresented (22% vs 7% expected, p < 0.0001). CONCLUSION: Prospectively collected times were considerably influenced by digit preference phenomenon. Studies that are not based on automatic time recordings and that have not evaluated and considered this bias should be interpretated with caution.

Clinical features of 1487 COVID-19 patients with outpatient management in the Greater Paris: the COVID-call study.

Clinical features of COVID-19 have been mostly described in hospitalized patients with and without ICU admission. Yet, up to 80% of patients are managed in an outpatient setting. This population is poorly documented. In France, health authorities recommend outpatient management of patients presenting mild-to-moderate COVID-19 symptoms. The aim of this study was to describe their clinical characteristics. The study took place in an emergency medical dispatching center located in the Greater Paris region. Patients included in this survey met confirmed COVID-19 infection criteria according to the WHO definition. We investigated clinical features and classified symptoms as general, digestive, ear-nose-throat, thoracic symptoms, and eye disease. Patients were included between March 24 and April 6 2020. 1487 patients included: 700 (47%) males and 752 (51%) females, with a median age of 44 (32-57) years. In addition to dry cough and fever reported in more than 90% of cases, the most common symptoms were general symptoms: body aches/myalgia (N = 845; 57%), headache (N = 824; 55%), and asthenia (N = 886; 60%); shortness of breath (N = 479; 32%) and ear-nose-throat symptoms such as anosmia (N = 415; 28%) and ageusia (N = 422; 28%). Chest pain was reported in 320 (21%) cases and hemoptysis in 41 (3%) cases. The main difference between male and female patients was an increased prevalence of ear-nose-throat symptoms as well as diarrhea, chest pains, and headaches in female patients. General symptoms and ear-nose-throat symptoms were predominant in COVID-19 patients presenting mild-to-moderate symptoms. Shortness of breath and chest pain were remarkably frequent.

COVID-19 epidemic in the Seine-Saint-Denis Department of Greater Paris: one month and three waves for a tsunami.

INTRODUCTION: Worldwide, the COVID-19 epidemic has put health systems to the test. The excess mortality is partly due to the influx of patients requiring hospitalization and intensive care. We propose that the chronology of epidemic spread gives a window of time in which hospitals can act to prevent reaching capacity. METHODS: The out-of-hospital SAMU Emergency Medical System in an entry point into the French health care system. We recorded the number of patients managed, of patients transferred to emergency departments (ED), and of mobile intensive care units (MICUs) dispatched. Each criterion was compared to the mean of the same criterion over the previous 5 years. The alert threshold which indicated a public health crisis was defined as a 20% increase compared to the 5-year mean. RESULTS: The reference period, from January 2015 to December 2019, included 3 381 611 calls, and 1 137 856 patients. The study period, from 17 February to 28 March 2020, included 166 888 calls, and 56 708 patients. The daily numbers of patients managed crossed the threshold on February 25, and increased until the end of the study period. The daily number of patients transferred to ED crossed the threshold on March 16, and increased until the end of the period. The daily number of MICUs dispatched crossed the threshold on March 15, and increased until the end of the period. CONCLUSION: The COVID-19 epidemic reached our department in three consecutive waves which overwhelmed the health care system. The first wave preceded by 30 days the massive arrival of critical patients. Health care systems must take advantage of this delay to prepare for the third wave.