Step 4 - "Can you still do the easiest job you have done in the past 15 years?"
Up to now, the focus has been primarily on determining what a person's documented medical conditions are and how severe they are. At Steps 4 and 5, the focus now shifts to vocational questions - questions about a person's ability to do a job. Step 4 looks at whether a person can still do the easiest job he or she did in the past fifteen years despite their medical problems.
At Step 4 Social Security considers whether a person's limitations prevent them from performing their "Past Relevant Work (PRW)" Past relevant work is work that a person has done within the past fifteen years for at least three months at full-time in exchange for pay. If Social Security determines that someone can still do the type of work that they have done in the past in spite of their medical conditions, their application for Social Security Disability benefits will be denied. If, on the other hand, Social Security determines that a person can't do the easiest job they have worked at in the past fifteen years, then we go to the last question of the 5-step evaluation process.
In our previous example, Mary's prior work was as a waitress. As a waitress, she was required to be on her feet most of the day and lift heavy trays. If Social Security concluded that Mary's back pain would require her to be off her feet most of the work-day, she would not be able to work as a waitress - her "PRW" - and her claim for disability benefits would move on to the last step in the 5-step evaluation process.
For more information see: 20 C.F.R. Section 404.1520(a)(4)(iii).