The opinion of the court was delivered by: VICTOR B. Kenton United States Magistrate Judge
MEMORANDUM OPINION AND ORDER (Social Security Case)
This matter is before the Court for review of the decision by the Commissioner of Social Security denying Plaintiff's application for disability benefits. Pursuant to 28 U.S.C. §636(c), the parties have consented that the case may be handled by the Magistrate Judge. The action arises under 42 U.S.C. §405(g), which authorizes the Court to enter judgment upon the pleadings and transcript of the Administrative Record ("AR") before the Commissioner. The parties have filed the Joint Stipulation ("JS"), and the Commissioner has filed the certified AR.
Plaintiff raises the following issues:
1. Whether the Administrative Law Judge ("ALJ") erred in finding that Plaintiff could perform her past relevant work; and
2. Is reversal the appropriate remedy in this case? (JS at 3.)
This Memorandum Opinion will constitute the Court's findings of fact and conclusions of law. After reviewing the matter, the Court concludes that for the reasons set forth, the decision of the Commissioner must be reversed.
Plaintiff's first issue, which questions whether the ALJ erred in finding that she could perform her past relevant work ("PRW"), breaks down into three discrete sub-issues. First, with regard to the assessment of Plaintiff's mental residual functional capacity ("MRFC"), Plaintiff argues error. Second, concerning Plaintiff's exertional limitations as relevant to her physical residual functional capacity ("PRFC"), she again asserts error. Finally, Plaintiff disputes the ALJ's credibility assessment concerning her subjective pain. The Court will address these issues separately.
I THE ALJ'S REJECTION OF THE ASSESSMENT OF PLAINTIFF'S TREATING PSYCHIATRIST, DR. LUSTIG, IS NOT SUPPORTED BY SUBSTANTIAL EVIDENCE
In his decision (AR 52-63), the ALJ determined Plaintiff's MRFC as follows: "She is moderately limited in her ability to understand and carry out detailed or complex tasks and instructions and in her ability to maintain concentration and attention." (AR 61.) In making this assessment, the ALJ rejected the contrary opinion of her treating psychiatrist, Dr. Lustig, based on one stated reason, to wit: "I give lesser weight to the opinion of Dr. Lustig, who appeared to base part of his opinion on the [Plaintiff's] physical condition rather than her mental impairment." (AR 62, exhibit citation omitted.)
In evaluating mental impairments, 20 C.F.R. §404.1520a(c)(3)(4) and §416.920a(c)(3)(4) mandate that consideration be given, among other things, to activities of daily living ("ADLs"), social functioning; concentration, persistence, or pace; and episodes of decompensation. These factors are generally analyzed in a Psychiatric Review Technique Form ("PRTF"). The PRTF is used at Step Three of the sequential evaluation to determine if a claimant is disabled under the Listing of Impairments; however, the same data must be considered at subsequent steps unless the mental impairment is found to be not severe at Step Two. See SSR 85-16.
20 C.F.R. §§404.1520a(c)(1) and 416.920a(c)(1) require consideration of "all relevant and available clinical signs and laboratory findings, the effects of your symptoms, and how your functioning may be affected by factors including, but not limited to, chronic mental disorders, structured settings, medication and other treatment."*fn1
SSR 85-16 suggests the following as relevant evidence:
"History, findings, and observations from medical sources (including psychological test results), regarding the presence, frequency, and intensity of hallucinations, delusions or paranoid tendencies; depression or elation; confusion or disorientation; conversion symptoms or phobias; psycho-physiological symptoms, withdrawn or bizarre behavior; anxiety or tension. Reports of the individual's activities of daily living and work activity, as well as testimony of third parties about the individual's performance and behavior. Reports from workshops, group homes, or similar assistive entities."
It is also required under §404.1520a(c)(2) and §416.920a(c)(2) that the ALJ must consider the extent to which the mental impairment interferes with an "ability to function independently, appropriately, effectively, and on a sustained basis" including "such factors as the quality and level of  overall functional performance, any episodic limitations [and] the amount of supervision or assistance  require[d]."
Pursuant to the September 2000 amendments to the regulations which modify 20 C.F.R. §404.1520a(e)(2) and §416.920a(e)(2), the ALJ is no longer required to complete and attach a PRTF. The revised regulations identify five discrete categories for the first three of four relevant functional areas: activities of daily living; social functioning; concentration, persistence or pace; and episodes of decomposition. These categories are None, Mild, Moderate, Marked, and Extreme. (§404.1520a(c)(3), (4).) In the decision, the ALJ must incorporate pertinent findings and conclusions based on the PRTF technique. §404.1520a(e)(2) mandates that the ALJ's decision must show "the significant history, including examination and laboratory findings, and the functional limitations that were considered in reaching a conclusion about the severity of the mental impairment(s). The decision must include a specific finding as to the degree of limitation in each of the functional areas described in paragraph (c) of this section."
The Step Two and Three analyses (see Decision at AR 53-54) are intended to determine, first, whether a claimant has a severe mental impairment (Step Two), and if so, whether it meets or equals any of the Listings (Step Three). It is also required under §404.1520a(c)(2) and §416.920a(c)(2) that the ALJ must consider the extent to which the mental impairment interferes with an "ability to function independently, appropriately, effectively, and on a sustained basis" including "such factors as the quality and level of  overall functional performance, any episodic limitations [and] the amount of supervision or assistance  require[d]."
These findings and conclusions are relevant to the Step Two and Three analysis of whether a claimant has a severe mental impairment, and if so, whether it meets or equals any of the Listings. (See 20 C.F.R. Part 4, subpart p, App. 1.) The discussion in Listing 12.00, "Mental Disorders," is relevant:
"The criteria in paragraphs B and C describe impairment-related functional limitations that are incompatible with the ability to do any gainful activity. The functional limitations in paragraphs B and C must be the result of the mental disorders described in the diagnostic ...