# You Need 4 Resources. Not 40.

> The four Step 1 resources that matter — First Aid, UWorld, Sketchy micro and pharm, Mehlman — and how USMLE Vault ties them together.

URL: https://usmlevault.com/blog/core-4.html
Canonical: https://usmlevault.com/blog/core-4.html

## Summary

Argues IMGs fail Step 1 by drowning in resources rather than lacking them, and reduces the stack to four: First Aid as the source of truth, UWorld for exam application, Sketchy for micro and pharm volume, and Mehlman conditionally for weak systems. Positions USMLE Vault as the connecting layer that attaches a page-by-page First Aid guide, concept walkthroughs, videos, MCQs, Anki and a daily schedule to each First Aid page. States the Vault is $97 lifetime with no subscription.

## Key facts

- Four necessities: First Aid, UWorld, Sketchy micro + pharm, Mehlman
- 60–70% of UWorld traces directly back to First Aid
- Mehlman is conditional — bring him in on systems where UWorld sits at or below 65%
- USMLE Vault is $97 lifetime, no subscription
- Each First Aid page in the Vault carries a high-yield guide, concept walkthroughs, attached videos, page-specific MCQs, and a page-by-page Anki deck
- Free trial is 3 days

## Covers

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## Source

USMLE Vault — https://usmlevault.com
Author: Dr. Marish Asudani

Updated: 2026-08-26