Figure 1. Case courtesy of Dr Muhammad Asadullah Munir, Radiopaedia.org. From the case rID: 78890
A 30-year-old female presents with left second finger pain with overlying erythema, warmth, and swelling the day after her cat bit her finger. She cannot fully extend the finger, it is tender and she has pain when it is passively extended. Her hand appears as shown above (Figure 1. Case courtesy of Kristina Kyle, MD).
Figure 1. Image prompt: AP view of the pelvis and left hip. Authors’ own images.
A 70-year-old male presents with left hip pain and inability to ambulate after a mechanical trip and fall. Examination demonstrates that the left lower extremity is shortened, abducted and externally rotated. Hip and pelvis x-rays are obtained (Figure 1).
A 29-year-old male presents with right shoulder pain, throbbing, and swelling. He states that a bulge has appeared over his right anterior shoulder recently (Image 1). While he was doing pushups today, he began to have numbness, tingling, and weakness in his right arm. While in the waiting room, his symptoms have completely resolved.
Image 1: Bedside ultrasound of the anterior shoulder at the site of the bulge. AA=axillary artery. AV=axillary vein. Author’s image.
An 80-year-old male presents with severe right arm pain after he tripped and fell down 2 steps. Examination shows deformity and swelling to his right upper arm. You obtain AP and lateral humerus x-rays as above.
Adolescent suicide rates in the United States, partly augmented by the COVID-19 pandemic, are steadily increasing [1, 2]. A commonly used screening tool is the 4-question Ask Suicide-Screening Questions (ASQ) instrument, which has a sensitivity and specificity of 60% and 92.7%, respectively, in predicting suicide-related events within 3 months. This was derived from a retrospective study of 15,003 pediatric patients (age 10-18 years) [3]. Given the morbidity and mortality associated with suicide attempts, is there a better screening tool with a higher sensitivity than 60%, while also maintaining adequate specificity? A higher sensitivity rate ensures that we have fewer misses.
In JAMA Psychiatry 2021, the Pediatric Emergency Care Applied Research Network (PECARN) researchers report derivation and external validation data for their suicide screening tool, called the Computerized Adaptive Screen for Suicidal Youth (CASSY) [4]. This publication was actually two studies in one: a derivation of the tool and then an external validation.
This paper assumes that the reader understands certain predictive analytics methodologies and test design concepts. Let’s briefly review some of the foundational terminology used:
A total of 6,536 adolescents (age 12-17 years) from 13 PECARN emergency departments were enrolled and a subset were randomly received follow-up in 3 months to assess for a suicide attempt. These patients responded to 92 questions on a computer tablet. Using a multidimensional item response theory approach, the more correlated questions (72) were used to create the CASSY tool.
A total of 4,050 adolescents from 14 PECARN emergency departments were enrolled, and all received 3-month follow-up assessing for a suicide attempt. These patients completed the CASSY tool, as well as a subset of questions from study 1 for comparison. The frequency of questions used in the adaptive screen are itemized in the paper.
Although there was strong study rigor by deriving and independently validating the tool in separate, multicenter populations, it should be noted that generalizability may be affected.
The CASSY tool accurately serves as a screening predictive tool for adolescents at risk for a suicide attempt in 3 months. Rather than having patients complete exhaustively long (and practically unfeasible) screening questions in the emergency department, this computerized adaptive tool required only a mean of 11 questions, which took a median time of 1.4 minutes (IQR 0.98-2.06 minutes) to complete.
We asked the authors this question, and the answer is in the podcast below.
Listen more with author Dr. Jacqueline Grupp-Phelan talking with ALiEM podcast host, Dr. Dina Wallin, about this landmark paper and behind-the-scenes issues not included on the paper.
This blog post was expert peer-reviewed by Drs. King and Grupp-Phelan, who authored the paper.
A 27-year-old female presents with left knee pain after a low-speed motor vehicle collision in which her knee hit the dashboard. She is tender over the patella without significant effusion and has an intact extensor mechanism. The above x-ray was obtained (Image 1. X-ray left knee. Case courtesy of Dr. M. Mourits, Radiopaedia.org, rID: 14476).