                    United States Court of Appeals
                           FOR THE EIGHTH CIRCUIT
                                   ___________

                                   No. 02-3854
                                   ___________

Carmen Lewis,                             *
                                          *
             Appellant,                   *
                                          *      Appeal from the United States
      v.                                  *      District Court for the
                                          *      Western District of Missouri.
Jo Anne B. Barnhart,                      *
Commissioner of Social Security,          *
                                          *
             Appellee.                    *

                                   ___________

                             Submitted: September 8, 2003

                                  Filed: December 30, 2003
                                   ___________

Before SMITH, LAY, and BRIGHT, Circuit Judges.
                            ___________

SMITH, Circuit Judge.

      Carmen Lewis applied for social security disability insurance benefits ("SSDI")
under 42 U.S.C. §§ 401–433 (2003) and supplemental security income benefits
("SSI") under 42 U.S.C. §§ 1381–1383c (2003), but the Social Security
Administration denied her application initially and on reconsideration. Lewis appeals
from an order of the district court1 affirming the Social Security Commissioner's
decision denying both SSI and SSDI. We affirm.

                                   I. Background
      Lewis's January 23, 1997, application alleged a disability onset date of
September 30, 1996. Lewis stated that she was unable to work because of a variety
of impairments, including back, knee, and ankle pain, major headaches, and asthma.
She alleges that the pain prevents her from performing any type of work.

       A hearing was held before an administrative law judge ("ALJ") on September
25, 1998. Lewis, who was thirty-eight years old at the time of the hearing, had
worked primarily in unskilled positions requiring semi-physical labor. She completed
the tenth grade and received a General Equivalency Diploma in 1985. Her past work
included kitchen helper, security guard, and assembly worker. She last worked in
1995.

       Regarding her physical impairments, Lewis testified that she had severe pain
in her lower back. The pain limited Lewis such that she could only stand comfortably
for thirty minutes, walk about one block, climb one flight of stairs, carry ten pounds,
and sit for about thirty minutes. Lewis also testified that she had problems with
muscle spasms in her legs and back, forcing her to lie down three to five times per
day for about an hour at a time. She stated that she had problems holding objects in
her hands. Additionally, Lewis testified that she had difficulty reaching over her head
with either arm, experienced swelling in her feet, knees, and hands several times per
week, experienced headaches, which lasted one to four hours, three to four times per
week, and had problems with her memory. Besides her pain allegations, Lewis also
described respiratory difficulties due to asthma and bronchitis. Lewis treated her


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       The Honorable Fernando J. Gaitan Jr., United States District Judge for the
Western District of Missouri.

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various pain and respiratory symptoms with medications, several of which made her
drowsy.

        Testifying as to her mental stability, Lewis stated that she had crying spells
once a week, had thoughts of suicide, and had problems coping with the recent deaths
of several family members. She testified that it was difficult for her to concentrate and
to finish tasks, and that she quickly became angry. Lewis claimed that she would
sweat and tremble two or three times per day. Regarding her activities, Lewis testified
that she did not go to the grocery store or go fishing as often as in the past. Lewis
testified that her daily activities consisted of washing dishes, doing laundry, cooking,
watching television, and reading.

       The ALJ found that Lewis's assertions of disabling pain were not fully credible.
Specifically, the ALJ determined that she had the physical ability to perform limited
exertional demands despite her alleged ankle, back, and knee pain, and headaches.
The ALJ concluded that Lewis could return to her previous work as an assembly
worker or, in the alternative, that jobs exist in the national economy that Lewis could
perform. Thus, the ALJ determined that Lewis was not disabled.

       On October 17, 2000, the Appeals Council of the Social Security
Administration denied Lewis's request for review of the ALJ's decision. The decision
of the Appeals Council stands as the final decision of the Commissioner. Lewis then
sought judicial review in the United States District Court for the Western District of
Missouri. The district court affirmed the Commissioner, and Lewis appeals.

       In this appeal, Lewis makes two arguments. First, she contends that the ALJ's
decision that she could return to her past relevant work was not supported by
substantial evidence. Second, she argues that the ALJ posed a defective hypothetical
question to the vocational expert because it did not include specific findings of the
consultative psychologist, as set forth in a November 1999 medical assessment.

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                                   II. Discussion
      On appeal, we review de novo the district court's grant of summary judgment
upholding the ALJ's denial of social security benefits. Box v. Shalala, 52 F.3d 168,
170 (8th Cir. 1995). "Our role is to determine whether the Secretary's decision is
supported by substantial evidence on the entire record." Id. (quoting Cook v. Bowen,
797 F.2d 687, 690 (8th Cir. 1986)). "Substantial evidence is less than a
preponderance, but enough that a reasonable mind might accept as adequate to
support a conclusion." Kelley v. Callahan, 133 F.3d 583, 587 (8th Cir. 1998) (citing
Lawrence v. Chater, 107 F.3d 674, 676 (8th Cir. 1997)). The review we undertake is
more than an examination of the record for the existence of substantial evidence in
support of the Commissioner's decision; we also take into account whatever in the
record fairly detracts from the decision. Id. (citing Cline v. Sullivan, 939 F.2d 560,
564 (8th Cir. 1991)).

      Title II of the Social Security Act provides for the payment of insurance
benefits to persons who suffer from a physical or mental disability, and Title XVI
provides for the payment of disability benefits to indigent persons. The Act further
provides that "an individual shall be determined to be under a disability [2] only if his
physical or mental impairment or impairments are of such severity that he is not only
unable to do his previous work but cannot, considering his age, education, and work
experience, engage in any other kind of substantial gainful work which exists in the
national economy . . . ." 42 U.S.C. § 423(d)(2)(A) (2003).

      The Secretary has established a five-step sequential evaluation process for
determining whether a person is disabled. 20 C.F.R. § 404.1520(a) (1986). The


      2
        Both titles of the Act define "disability" as the "inability to engage in any
substantial gainful activity by reason of any medically determinable physical or
mental impairment which can be expected to result in death or which has lasted or can
be expected to last for a continuous period of not less than 12 months . . . ." 42 U.S.C.
§ 423(d)(1)(A) (2003).

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Commissioner determines: (1) whether the claimant is engaged in substantial gainful
activity, and if he is, disability benefits are denied; (2) whether the claimant has a
medically severe impairment or combination of impairments that significantly limits
the claimant's physical or mental ability to perform basic work activities, including
walking, standing, sitting, lifting, pushing, pulling, reaching, carrying, handling,
seeing, hearing, speaking, understanding, carrying out and remembering simple
instructions, use of judgment, responding appropriately to supervision, co-workers,
and usual work situations, and dealing with changes in a routine work setting; (3)
whether the impairment is equivalent to one of a number of listed impairments that
the Secretary acknowledges are so severe as to preclude substantial gainful activity,
and if so, the claimant is disabled; (4) whether the impairment prevents the claimant
from performing work he has performed in the past; (5) if the claimant is able to
perform his previous work, he is not disabled; however, if the claimant cannot
perform past work, the burden shifts to the Commissioner to prove that the claimant
is able to perform other work in the national economy in view of [her] age, education,
and work experience. See Bowen v. Yuckert, 482 U.S. 137, 140–42 (1987); Baker v.
Apfel, 159 F.3d 1140, 1143–44 (8th Cir. 1998); Kelley, 133 F.3d at 587–88; 20 C.F.R.
§ 404.1520(a), (b), (c), (d), (e) (1986).

        Although it was not required in this case, the ALJ's analysis proceeded through
all five steps of the claim-evaluation process. The ALJ found that Lewis satisfied the
requirements of step one and two and proceeded to the remaining steps of the process.
Because Lewis's impairments did not meet the criteria for any listed impairments in
step three, the ALJ proceeded to step four. See Yuckert, 482 U.S. at 141; Lauer v.
Apfel, 245 F.3d 700, 703–04 (8th Cir. 2001). Step four requires the ALJ to consider
the claimant's residual functional capacity ("RFC") and the physical and mental
demands of the claimant's past work. Nimick v. Sec'y of Health and Human Servs.,
887 F.2d 864, 866 (8th Cir. 1989). When determining a claimant's RFC, the ALJ's
determination must be supported by medical evidence that addresses the claimant's
ability to function in the workplace. Krogmeier v. Barnhart, 294 F.3d 1019, 1023 (8th

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Cir. 2002). RFC is a medical question defined wholly in terms of the claimant's
physical ability to perform exertional tasks or, in other words, "what the claimant can
still do" despite his or her physical or mental limitations. Bradshaw v. Heckler, 810
F.2d 786, 790 (8th Cir. 1987); 20 C.F.R. § 404.1520(e) (1986). Under this step, the
ALJ is required to set forth specifically a claimant's limitations and to determine how
those limitations affect her RFC. Ingram v. Chater, 107 F.3d 598, 604 (8th Cir.
1997).

       The ALJ reviewed the medical evidence and determined that Lewis possessed
the RFC to return to her past work as an assembly worker. Lewis's medical records
included reports from three physicians. First, Edna C. DeCastro, M.D., performed a
consultative disability examination on Lewis on August 26, 1997. Dr. DeCastro noted
that Lewis was alert, oriented, pleasant, cooperative, and well-developed. Although
Lewis complained of severe disabling pain in her joints, the doctor noted that Lewis's
joints showed no evidence of synovitis, swelling, or tenderness, her knees showed no
crepitus, and she had full passive ranges of motion of all her joints. Dr. DeCastro
indicated that Lewis's chronic low back pain, headaches, and asthma were caused by
her lack of daily exercise and abuse of tobacco.

       Second, Zubin G. Khubchandani, M.D., at the Truman Medical Center
Orthopedic Clinic, examined Lewis in January 1998. Lewis complained of low back
pain that had worsened after traffic accidents in 1990 and 1996. Lewis reported some
relief with pain medications, but stated that she was unable to work because of the
constant pain. On examination, Lewis had tenderness to palpation over the posterior
superior iliac spine bilaterally. Dr. Khubchandani found that Lewis had good motor
strength in her legs, normal light touch sensation with the exception of some
decreased sensation over the little toes, normal patellar and knee jerk reflexes, and
negative straight leg raising bilaterally. Dr. Khubchandani diagnosed low back pain
and recommended that Lewis stop smoking because smokers have an increased risk
for chronic back pain. Also, similar to Dr. DeCastro's advice, Dr. Khubchandani

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advised that Lewis undergo physical therapy for back strengthening and stretching,
and take part in aerobic activity such as swimming, cycling, and walking. The doctor
stated that he could not offer Lewis anything surgical and explained that chronic-low
back pain is lessened strictly by management.

       Third, under the direction of psychologist Dr. Minnie Koresko, Lewis
underwent a post-hearing neuropsychological evaluation in November 1999. The
results of her evaluation indicated that Lewis could perform satisfactorily in a job that
was routine and in a work environment that did not offer multiple stimuli that would
cause Lewis's attention to divert.3

      Relying on the opinion of the medical doctors and on Lewis's own testimony,
the ALJ concluded that Lewis had the RFC to return to her previous job as an
assembler. The ALJ determined that Lewis could ameliorate her alleged disabling
conditions by participating in aerobics and ceasing to smoke cigarettes.

      However, proceeding to step five, the ALJ also found–based on the vocational
expert's testimony–that there were a significant number of jobs in the area for a
worker with Lewis's RFC.

               A. Substantial Evidence to Support the ALJ's Decision
       The record provides substantial evidence on the record as a whole to support
the ALJ's decision that Lewis can return to her past work as an assembler. According
to the vocational expert, the physical and mental demands of an assembly worker are


      3
        With regard to Lewis's cognitive functions, Dr. Koresko indicated that Lewis
had the ability to learn and adapt to unfamiliar situations and comprehend verbal
communication. Dr. Koresko also indicated that Lewis had adequate intellectual
functioning for jobs that did not require complex problem solving, decision making,
or sustained focus and attention. On the memory test, Lewis's performance was
normal.

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limited. Assembly work as customarily performed in the national economy is often
unskilled, non-detailed, and not shown to entail duties beyond light exertion. Lewis
contends that she is unable to work as an assembly worker because of the severe pain
she experiences in her knees, back, and ankles.

       The ALJ discounted Lewis's subjective allegations of disabling pain. "[T]he
ALJ must consider the claimant's prior work history; daily activities; duration,
frequency and intensity of pain; dosage, effectiveness and side effects of medication;
precipitating and aggravating factors; and functional restrictions" when evaluating
a claimant's alleged pain. Baker, 159 F.3d at 1144. When analyzing this criteria, the
ALJ makes an express credibility determination of the claimant's allegation and
discounts those subjective pain complaints that are not credible. Polaski v. Heckler,
739 F.2d 1320, 1322 (8th Cir. 1984). When rejecting a claimant's complaints of pain,
the ALJ's express credibility determination must detail the reasons for discrediting the
testimony and set forth the inconsistencies found. Baker, 159 F.3d at 1144.

       Lewis's pain complaints are not supported by the record on the whole;
however, the evidence does support the ALJ's decision to discount Lewis's
complaints. Both Dr. DeCastro and Dr. Khubchandani concluded that Lewis could
reduce the pain that she felt in her joints and the uncomfortable effects of asthma if
she refrained from smoking and exercised daily. Lewis has failed to adhere to this
advice. Furthermore, Dr. Koresko concluded that Lewis could perform satisfactorily
in a job that was routine and in a work environment which did not offer multiple
stimuli that would divert Lewis's attention. Moreover, Lewis's medical records show
that she has full range-of-motion in her joints, normal back curvature, and is alert,
oriented, able to sit, stand, walk, lift, and carry. The doctors indicated all that was
required for Lewis to successfully manage her alleged pain was to participate in
aerobics and stop smoking. Instead, Lewis's own actions discredit her disability
allegations because she continues to smoke cigarettes daily and does not exercise.



                                          -8-
       The ALJ found that Lewis was not disabled within the meaning of the Social
Security Act. Specifically, the ALJ found that Lewis has the RFC to perform the
exertional demands of sedentary work in that she is able to lift and carry up to twenty
pounds occasionally; to stand or walk thirty minutes at a time for six hours of an eight
hour day; and to sit thirty minutes at a time for six hours of an eight hour day. The
ALJ noted that Lewis's capacity for the full range of light work is diminished by non-
exertional and psychologically-based limitations in that she sustains some fatigue
from her medications and experiences some pain. Lewis is restricted from more than
occasional stooping, crouching, crawling, balancing, kneeling, and other forms of
climbing. The ALJ found that Lewis was moderately limited in her ability to
understand, remember, carry out detailed instructions, and maintain attention and
concentration for extended periods. The ALJ's conclusion is supported by substantial
evidence on the record as a whole that Lewis can do "light work" as an assembler.

      Once we have found that there is substantial evidence on the record as a whole
to support the ALJ's decision concerning a claimant's disability, the five-step analysis
need go no further. Baker, 159 F.3d at 1143–44. Vocational expert testimony is not
required at step four where the claimant retains the burden of proving she cannot
perform her prior work. See Banks v. Massanari, 258 F.3d 820, 827 (8th Cir. 2001)
(en banc); Gaddis v. Chater, 76 F.3d 893, 896 (8th Cir. 1996); Barrett v. Shalala, 38
F.3d 1019, 1024 (8th Cir. 1994). Therefore, Lewis's claim that the ALJ posed a
defective hypothetical to the vocational expert is moot.

                                   III. Conclusion
        Because we hold that substantial evidence on the record as a whole supports
the ALJ's decision that Lewis retained the RFC to return to her past relevant work,
there is no need to address Lewis's second argument. Accordingly, the judgment of
the district court is affirmed.
                          ______________________________



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