Which laboratory test is most helpful in diagnosing Duchenne muscular dystrophy (DMD)?  

Which type of viral hepatitis is most commonly transmitted through the fecal-oral route and is often associated with contaminated food or water?

A 13-year-old recently recovered from a streptococcal pharyngitis infection. Two weeks later, she presents with the sudden appearance of small, drop-like, salmon-colored, scaly lesions scattered across her trunk and proximal extremities. What is the most likely diagnosis?

What is the primary genetic defect in osteogenesis imperfecta?

A 7-year-old child presents with multiple hypopigmented, scaly patches on the cheeks. The lesions are not itchy. Which of the following is the most likely diagnosis?

What screening should begin by age 1 in children with Down syndrome?

Which of the following clinical features is most characteristic of albinism?

A newborn is delivered with a suspected open neural tube defect. What is the most appropriate initial step in the postnatal assessment and diagnosis?  

Which of the following would be the most concerning finding for physical abuse?

A 9-year-old presents with a smooth, round, non-scarring bald patch on the scalp. No scaling or erythema is seen. What is the most likely diagnosis?