Appendix I. Summary Tables of Treatment Outcomes
Table A. Acute Low Back Pain: Evidence Summary of Treatments up to Six Weeks
Reference line / Treatment or system / Number ofstudy arm observations / Studies used (see Appendix 2) / Patients observations at start / Patient observations at study's end / g (95% CI) / pB / Evidential support over shamc
Single therapies
1 / Osteopathic SMT / 7 / 1 2 / 153 / 151 / 0.79 (-1.12 to 2.71) / 0.50 / b
2 / Physical therapist SMT / 11 / 3 4 5 6 7 8 9 10 / 655 / 581 / 2.04 (0.93 to 3.15) / 0.91 / b
3 / Chiropractic SMT / 6 / 11 12 13 14 15 16 17 18 / 408 / 407 / 1.48 (-1.16 to 4.12) / 0.61 / b
4 / Chiropractic Flexion-Distraction / NA / NA / NA / NA / NA / NA / NA
5 / Medical SMT / 6 / 19 20 21 22 / 91 / 91 / 0.97 (-0.73 to 2.68) / 0.51 / b
6 / Mixed SMT / 3 / 23 24 25 / 65 / 65 / 2.57 (0.32 to 4.83) / 1.00 / b
7 / Back school classes / 7 / 3 4 12 14 23 24 / 377 / 266 / 2.70 (-1.17 to 6.56) / 0.86 / b
8 / Usual medical and analgesic / 6 / 7 10 16 19 / 148 / 148 / 0.76 (-0.79 o 2.31) / 0.21 / b
9 / Attended physiotherapy modalities / 16 / 3 5 6 7 8 10 1113 14 15 16 17 22 / 837 / 734 / 1.83 (-0.35 to 4.01) / 0.75 / b
10 / Self care / 11 / 2 4 13 15 16 / 325 / 325 / 0.65 (-2.70 to 3.99) / 0.33 / b
11 / Sham treatments / 9 / 1 7 16 11 18 21 22 26 / 256 / 250 / 1.40 (0.06 to 2.75) / 0.68 / Comparison
12 / No treatment: waiting list control / NA / NA / NA / NA / NA / NA / NA
13 / Unattended physiotherapy modalities / 6 / 1 4 9 13 15 / 233 / 231 / 0.69 (-5.00 to 6.36) / 0.39 / b
14 / Bonesetting / NA / NA / NA / NA / NA / NA / NA
Therapies categories
15 / All manipulation groups / 30 / 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 18 19 20 21 22 23 24 25 / 1085 / 1074 / 1.56 (1.22 to 4.34) / 0.72 / b
16 / All control groups combined / 10 / 1 7 11 16 20 21 25 / 354 / 247 / 1.92 (0.26 to 3.59) / 0.80 / b
17 / All medical management combined / 15 / 7 10 16 19 / 411 / 411 / 0.75 (-2.15 to 3.65) / 0.32 / b
18 / Combined physiotherapies / 19 / 1 3 4 5 6 7 8 9 10 11 13 14 15 16 18 22 / 958 / 880 / 1.65 (-1.84 to 5.14) / 0.65 / b
19 / Exercise and back school / 9 / 3 4 12 14 23 24 / 416 / 305 / 2.31 (-1.06 to 5.68) / 0.78 / b
20 / Whole system care / 6 / 6 7 8 / 274 / 274 / 1.21 (0.06 to 2.35) / 0.76 / b
a NA = no studies available for these conditions b Evidence equal to or favoring sham / cEvidential support interpretation: -1 is weak, -2 moderate,
-3 strong, -4 extremely strong evidence favoring treatment
Table B. Acute Low Back Pain: Evidence Summary of Treatments after Six Weeks and Up to One Year
Reference line / Treatment or system / Number ofstudy arm observations / Studies used (see Appendix 2) / Patients observations at start / Patient observations at study's end / g (95% CI) / pB / Evidential support over shamc
Single therapies
1 / Osteopathic SMT / 2 / 1 25 / 157 / 154 / 2.76 (0.71 to 4.81) / 0.68 / b
2 / Physical therapist SMT / 3 / 7 10 11 / 276 / 276 / 2.27 (2.06 to 2.47) / 0.69 / b
3 / Chiropractic SMT / 8 / 11 14 16 17 18 27 28 / 551 / 551 / 1.50 (-2.03 to 5.03) / 0.80 / b
4 / Chiropractic Flexion-Distraction / NA / NA / NA / NA / NA / NA / NA
5 / Medical SMT / 1 / 29 30 31 / 48 / 48 / 2.98 (1.82 to 4.14) / 1.00 / b
6 / Mixed SMT / 4 / 32 / 1150 / 1013 / 0.59 (-2.73 to 3.90) / 0.13 / b
7 / Back school / 6 / 4 14 16 32 / 663 / 663 / 1.53 (-0.48 to 3.54) / 0.59 / b
8 / Usual/Analgesic / 8 / 7 10 16 29 30 / 264 / 264 / 1.82 (-0.20 to 3.85) / 0.68 / b
9 / Attended physiotherapy modalities / 10 / 7 10 11 14 16 18 28 / 604 / 592 / 2.01 (0.20 to 3.81) / 0.85 / b
10 / Self-care / 3 / 4 16 / 215 / 215 / 1.24 (-0.27 to 2.76) / 0.79 / b
11 / Sham treatments / 8 / 1 7 16 17 31 / 225 / 226 / 1.64 (-0.01 to 3.29) / 0.59 / Comparison
12 / No treatment: Waiting list control / NA / NA / NA / NA / NA / NA / NA
13 / Unattended physiotherapy modalities / 3 / 1 4 27 / 233 / 226 / 1.78 (-3.47 to 7.04) / 0.94 / b
14 / Bonesetting / NA / NA / NA / NA / NA / NA / NA
Therapy categories
15 / All manipulation groups / 16 / 1 7 10 11 14 16 18 26 27 28 29 30 31 32 / 1076 / 1073 / 2.34 (-1.10 to 5.79) / 0.84 / b
16 / All control groups combined / 7 / 1 7 16 31 / 177 / 178 / 1.78 (-0.05 to 3.60) / 0.65 / b
17 / All medical management combined / 10 / 7 10 16 26 29 30 / 438 / 438 / 1.78 (-0.25 to 3.80) / 0.77 / b
18 / Combined physiotherapies / 12 / 1 4 7 10 11 14 16 18 28 / 783 / 764 / 2.08 (-0.70 to 4.86) / 0.93 / b
19 / Exercise and back school / 6 / 4 14 16 32 / 663 / 663 / 1.53 (-0.48 to 3.54) / 0.59 / b
20 / Whole system care / 10 / 7 32 / 1754 / 1617 / 0.59 (0.37 to 0.82) / 0.13 / b
a NA = no studies available for these conditions b Evidence equal to or favoring sham / cEvidential support interpretation: -1 is weak, -2 moderate,
-3 strong, -4 extremely strong evidence favoring treatment
Table C. Chronic Low Back Pain: Evidence Summary of Treatments up to Six Weeks
Reference line / Treatment or system / Number ofstudy arm observations / Studies used (see Appendix 2) / Patients observations at start / Patient observations at study's end / g (95% CI) / pB / Evidential support over shamc
Single therapies
1 / Osteopathic SMT / 1 / 33 34 / 55 / 55 / -0.02 (-0.60 to 0.56) / 0.00 / b
2 / Physical therapist SMT / 1 / 35 / 8 / 8 / 4.24 (4.05 to 4.44) / 1.00 / -0.81
3 / Chiropractic SMT / 4 / 16 36 37 38 / 197 / 177 / 1.02 (-1.17 to 3.22) / 0.63 / -0.34
4 / Chiropractic Flexion-Distraction / 3 / 39 40 / 333 / 318 / 0.85 (-0.58 to 2.28) / 0.53 / -0.17
5 / Medical SMT / 2 / 20 41 / 52 / 52 / 1.04 (0.69 to 1.39) / 0.83 / -0.62
6 / Mixed SMT / 0 / NAa / NAa / NAa / NAa / NAa / NAa
7 / Back school / 6 / 16 35 37 39 42 43 / 251 / 220 / 0.58 (-2.91 to 4.06) / 0.15 / b
8 / Usual/Analgesic / 2 / 16 36 / 67 / 58 / 1.34 (-0.10 to 2.79) / 1.00 / -0.80
9 / Attended physiotherapy modalities / 3 / 16 42 43 / 85 / 83 / 0.84 (-2.45 to 4.13) / 0.67 / -0.40
10 / Self-care / 1 / 35 / 10 / 10 / 0.20 (-1.41 to 1.80) / 0.01 / b
11 / Sham treatments / 6 / 16 20 33 34 37 38 41 / 160 / 152 / 0.85 (-1.03 to 2.72) / 0.45 / Comparison
12 / No treatment: Waiting list control / 1 / 33 34 / 34 / 34 / -0.62 (-1.40 to 0.15) / 0.00 / NAa
13 / Unattended physiotherapy modalities / 2 / 40 / 188 / 188 / 0.59 (0.16 to 1.01) / 0.11 / b
14 / Bonesetter SMT / 2 / 42 43 / 89 / 83 / 0.88 (-2.97 to 4.72) / 0.57 / -0.24
Therapy categories
15 / All manipulation groups / 6 / 16 20 33 34 35 37 38 41 42 43 / 140 / 137 / 1.54 (-0.63 to 3.70) / 0.70 / -0.44
16 / All control groups / 4 / 16 25 33 34 37 38 41 / 81 / 73 / 1.09 (-1.36 to 3.54) / 0.65 / -0.38
17 / Medical management / 1 / 16 36 / 15 / 15 / 1.14 (-1.10 to 3.37) / 1.00 / -0.80
18 / Modalities / 5 / 16 40 42 43 / 270 / 270 / 0.83 (-1.05 to 2.71) / 0.52 / -0.16
19 / Exercise and back school / 6 / 16 35 37 39 42 43 / 395 / 369 / 0.65 (-2.22 to 3.53) / 0.17 / b
20 / SMT with clinical management / 8 / 41 42 43 / 308 / 295 / 0.70 (0.01 to 1.40) / 0.42 / b
a NA = no studies available for these conditions b Evidence equal to or favors sham / c Evidential support interpretation: -1 is weak, -2 moderate,
-3 strong, -4 extremely strong evidence favoring treatment
Table D. Chronic Low Back Pain: Evidence Summary of Treatments after Six Weeks and Up to One Year
Reference line / Treatment or system / Number ofstudy arm observations / Studies used (see Appendix 2) / Patients observations at start / Patient observations at study's end / g (95% CI) / pB / Evidential support over shamc
Single therapies
1 / Osteopathic SMT / 2 / 33 34 44 / 63 / 63 / 1.31 (-0.64 to 3.27) / 0.50 / -0.09
2 / Physical therapist SMT / 1 / 45 / 50 / 50 / 0.72 (-1.23 to 2.68) / 0.20 / b
3 / Chiropractic SMT / 4 / 16 46 / 95 / 95 / 1.07 (-0.88 to 3.03) / 0.64 / -0.33
4 / Chiropractic Flexion-Distraction / 3 / 39 40 / 219 / 192 / 0.85 (-1.10 to 2.81) / 0.40 / b
5 / Medical SMT / 1 / 41 / 40 / 40 / 1.41 (-0.54 to 3.37) / 1.00 / -0.78
6 / Mixed SMT / 2 / 47 / 96 / 96 / 1.44 (-0.51 to 3.40) / 1.00 / -0.78
7 / Back school classes / 7 / 16 39 43 45 / 392 / 320 / 2.29 (0.33 to 4.25) / 0.64 / -0.33
8 / Usual medical and analgesic / 6 / 16 36 46 47 / 169 / 169 / 1.23 (-0.72 to 3.19) / 0.61 / -0.28
9 / Attended physiotherapy modalities / 4 / 16 43 45 / 101 / 98 / 1.12 (-0.83 to 3.08) / 0.51 / -0.12
10 / Self care / 0 / NAa / NAa / NAa / NAa / NAa / NA
11 / Sham treatments / 5 / 2 33 34 44 47 / 95 / 95 / 0.77 (0.37 to 1.16) / 0.46 / Comparison
12 / No treatment: waiting list control / 2 / 33 34 45 / 84 / 84 / -0.13 (-2.09 to 1.82) / 0.00 / b
13 / Unattended physiotherapy modalities / 1 / 40 / 78 / 78 / 1.28 (-0.68 to 3.24) / 0.10 / b
14 / Bonesetting / 1 / 43 / 44 / 44 / 0.76 (-1.19 to 2.72) / 0.23 / b
Therapy categories
15 / All manipulation groups / 11 / 16 33 34 41 42 43 44 45 46 / 663 / 600 / 1.07 (-0.04 to 2.18) / 0.61 / -0.42
16 / All control groups combined / 7 / 16 33 34 41 44 45 / 179 / 179 / 0.51 (-1.45 to 2.47) / 0.54 / -0.16
17 / All medical management combined / 5 / 16 36 46 47 / 158 / 158 / 0.57 (-1.38 to 2.53) / 0.53 / -0.14
18 / Combined physiotherapies / 6 / 16 40 43 45 / 101 / 98 / 1.05 (-0.90 to 3.01) / 0.54 / -0.17
19 / Exercise plus back school / 8 / 16 39 43 45 / 470 / 398 / 2.08 (0.12 to 4.04) / 0.65 / -0.35
20 / Whole systems / 5 / 41 43 46 / 194 / 189 / 0.70 (-0.18. to 1.54) / 0.30 / b
a NA = no studies available for these conditions b Evidence equal to or favoring sham / cEvidential support interpretation: -1 is weak, -2 moderate,
-3 strong, -4 extremely strong evidence favoring treatment
Appendix II. List of References Used in Analysis
ANALYSIS REFERENCES
1. Gibson T, Grahame R, Harkness J, Woo P, Blagrave P, Hills R. Controlled comparison of short-wave diathermy treatment with osteopathic treatment in non-specific low back pain. Lancet. Jun 1 1985; 1(8440):1258-1261.
2. MacDonald RS, Bell CMJ. An open controlled assessment of osteo- pathic manipulation in nonspecific low-back pain. Spine. 1990; 15:364–370.
3. Bergquist-Ullman M, Larsson U. Acute low back pain in industry. A controlled prospective study with special reference to therapy and confounding factors.ActaOrthop Scand. 1977(170):1-117.
4. Coxhead CE, Inskip H, Meade TW, North WR, Troup JD. Multicentre trial of physiotherapy in the management of sciatic symptoms.Lancet. May 16 1981; 1(8229):1065-1068.
5. Farrell JP, Twomey LT. Acute low back pain. Comparison of two conservative treatment approaches. Med J Aust. Feb 20 1982; 1(4):160-164.
6. Kinalski R, Kuwik W, Pietrzak D. The comparison of the results of manual therapy versus physiotherapy methods used in treatment of patients with low back pain syndromes.Manual Med. 1989; 4:44–46.
7. Koes BW, Bouter LM, van Mameren H, et al. A blinded randomized clinical trial of manual therapy and physiotherapy for chronic back and neck complaints: physical outcome measures. J Manipulative PhysiolTher. Jan 1992; 15(1):16-23.
8. Mathews JA, Mills SB, Jenkins VM, et al. Back pain and sciatica: controlled trials of manipulation, traction, sclerosant and epidural injections. Br J Rheumatol.Dec 1987; 26(6):416-423.
9. Rasmussen GG. Manipulation in treatment of low back pain: a randomized clinical trial. ManuelleMedizin. 1979; 1:8-10.
10. Waterworth RF, Hunter IA. An open study of diflunisal, conservative and manipulative therapy in the management of acute mechanical low back pain. . NZ Med J 1985; 98(779):372–375.
11. Cherkin DC, Deyo RA, Battie M, Street J, Barlow W. A comparison of physical therapy, chiropractic manipulation, and provision of an educational booklet for the treatment of patients with low back pain.N Engl J Med. Oct 8 1998; 339(15):1021-1029.
12. Herzog W, Conway PJW, Willcox BJ. Effects of different treatment modalities on gait symmetry and clinical measures for sacroiliac joint patients. J Manipulative PhysiolTher1991; 14:104-109.
13. Hsieh CY, Phillips RB, Adams AH, Pope MH. Functional outcomes of low back pain: comparison of four treatment groups in a randomized controlled trial. J Manipulative PhysiolTher. Jan 1992; 15(1):4-9.
14. Hsieh CY, Adams AH, Tobis J, et al. Effectiveness of four conservative treatments for subacute low back pain: a randomized clinical trial. Spine (Phila Pa 1976).Jun 1 2002; 27(11):1142-1148.
15. Pope MH, Phillips RB, Haugh LD, Hsieh CY, MacDonald L, Haldeman S. A prospective randomized three-week trial of spinal manipulation, transcutaneous muscle stimulation, massage and corset in the treatment of subacute low back pain. Spine (Phila Pa 1976).Nov 15 1994; 19(22):2571-2577.
16. Postacchini F, Facchini M, Palieri P. Efficacy of various forms of conservative treatment in low back pain: a comparative study. Neuro-Orthopedics. 1988; 6:28–35.
17. Santilli V, Beghi E, Finucci S. Chiropractic manipulation in the treatment of acute back pain and sciatica with disc protrusion: a randomized double-blind clinical trial of active and simulated spinal manipulations. Spine J. Mar-Apr 2006; 6(2):131-137.
18. Skargren EI, Oberg BE, Carlsson PG, Gade M. Cost and effectiveness analysis of chiropractic and physiotherapy treatment for low back and neck pain. Six-month follow- up.Spine (Phila Pa 1976).Sep 15 1997; 22(18):2167-2177.
19. Evans DP, Burke MS, Lloyd KN, Roberts EE, Roberts GM. Lumbar spinal manipulation on trial. Part I--clinical assessment. RheumatolRehabil. Feb 1978; 17(1):46-53.
20. Glover JR, Morris JG, Khosla T. Back pain: a randomized clinical trial of rotational manipulation of the trunk. Br J Ind Med. Jan 1974; 31(1):59-64.
21. Hadler NM, Curtis P, Gillings DB, Stinnett S. A benefit of spinal manipulation as adjunctive therapy for acute low-back pain: a stratified controlled trial. Spine (Phila Pa 1976).Sep 1987; 12(7):702-706.
22. Wreje U, Nordgren B, Aberg H. Treatment of pelvic joint dysfunction in primary care - a controlled study Scand J Prim Health care 1992; 10:310–315.
23. Delitto A, Cibulka MT, Erhard RE, Bowling RW, Tenhula JA. Evidence for use of an extension-mobilization category in acute low back syndrome: a prescriptive validation pilot study. PhysTher. Apr 1993; 73(4):216-222; discussion 223-218.
24. Erhard RE, Delitto A, Cibulka MT. Relative effectiveness of an extension program and a combined program of manipulation and flexion and extension exercises in patients with acute low back syndrome. PhysTher. Dec 1994; 74(12):1093-1100.
25. Godfrey CM, Morgan PP, Schatzker J. A randomized trial of manipulation for low-back pain in a medical setting.Spine (Phila Pa 1976).Apr 1984; 9(3):301-304.
26. Andersson GB, Lucente T, Davis AM, Kappler RE, Lipton JA, Leurgans S. A comparison of osteopathic spinal manipulation with standard care for patients with low back pain.N Engl J Med. Nov 4 1999; 341(19):1426-1431.
27. Cramer GD, Humphreys CR, Hondras MA, McGregor M, Triano JJ. The Hmax/Mmax ratio as an outcome measure for acute low back pain.J Manipulative PhysiolTher. Jan 1993; 16(1):7-13.
28. Skargren EI, Oberg BE. Predictive factors for 1-year outcome of low-back and neck pain in patients treated in primary care: comparison between the treatment strategies chiropractic and physiotherapy. Pain. Aug 1998; 77(2):201-207.
29. Blomberg S, Svardsudd K, Mildenberger F. A controlled, multicentre trial of manual therapy in low-back pain. Initial status, sick-leave and pain score during follow-up. Scand J Prim Health Care.Sep 1992; 10(3):170-178.
30. Blomberg S, Hallin G, Grann K, Berg E, Sennerby U. Manual therapy with steroid injections--a new approach to treatment of low back pain. A controlled multicenter trial with an evaluation by orthopedic surgeons.Spine. Mar 1 1994; 19(5):569-577.
31. Hoehler FK, Tobis JS, Buerger AA. Spinal manipulation for low back pain.JAMA. May 8 1981; 245(18):1835-1838.
32. UK BEAM TT. United Kingdom back pain exercise and manipulation (UK BEAM) randomised trial: effectiveness of physical treatments for back pain in primary care. BMJ. Dec 11 2004; 329(7479):8.
33. Licciardone JC, Stoll ST, Fulda KG, et al. Osteopathic manipulative treatment for chronic low back pain: a randomized controlled trial. Spine (Phila Pa 1976).Jul 1 2003; 28(13):1355-1362.
34. Licciardone JC, Brimhall AK, King LN. Osteopathic manipulative treatment for low back pain: a systematic review and meta-analysis of randomized controlled trials. BMC MusculoskeletDisord. 2005; 6:43.
35.Zylbergold RS, Piper MC. Lumbar disc disease: comparative analysis of physical therapy treatments. Arch Phys Med Rehabil.Apr 1981; 62(4):176-179.
36. Bronfort G, Goldsmith CH, Nelson CF, Boline PD, Anderson AV. Trunk exercise combined with spinal manipulative or NSAID therapy for chronic low back pain: a randomized, observer-blinded clinical trial. J Manipulative PhysiolTher. Nov-Dec 1996; 19(9):570-582.
37. Triano JJ, McGregor M, Hondras MA, Brennan PC. Manipulative therapy versus education programs in chronic low back pain.Spine (Phila Pa 1976).Apr 15 1995; 20(8):948-955.
38. Waagen GN, Haldeman S, Cook G, Lopez D, DeBoer KF. Short term trial of chiropractic adjustments for the relief of chronic low back pain. Manual Medicine. 1986; 2:63-67.
39. Cambron JA, Gudavalli MR, Hedeker D, et al. One-year follow-up of a randomized clinical trial comparing flexion distraction with an exercise program for chronic low-back pain. J Altern Complement Med. Sep 2006; 12(7):659-668.
40. Gudavalli MR, Cambron JA, McGregor M, et al. A randomized clinical trial and subgroup analysis to compare flexion-distraction with active exercise for chronic low back pain.Eur Spine J. Jul 2006; 15(7):1070-1082.
41. Ongley MJ, Klein RG, Dorman TA, Eek BC, Hubert LJ. A new approach to the treatment of chronic low back pain.Lancet. Jul 18 1987; 2(8551):143-146.
42. Hemmila HM, Keinanen-Kiukaanniemi SM, Levoska S, Puska P. Does folk medicine work? A randomized clinical trial on patients with prolonged back pain. Arch Phys Med Rehabil.Jun 1997; 78(6):571-577.
43. Hemmila HM, Keinanen-Kiukaanniemi SM, Levoska S, Puska P. Long-term effectiveness of bone-setting, light exercise therapy, and physiotherapy for prolonged back pain: a randomized controlled trial. J Manipulative PhysiolTher. Feb 2002; 25(2):99-104.
44. Cleary C, Fox JP. Menopausal symptoms: an osteopathic investigation. Complementary Therapies in Medicine.1994; 2:181-186.
45. Timm KE. A randomized-control study of active and passive treatments for chronic low back pain following L5 laminectomy.J Orthop Sports PhysTher. Dec 1994; 20(6):276- 286.
46. Wilkey A, Gregory M, Byfield D, McCarthy PW. A comparison between chiropractic management and pain clinic management for chronic low-back pain in a national health service outpatient clinic. J Altern Complement Med. Jun 2008; 14(5):465-473.
47. Niemisto L, Lahtinen-Suopanki T, Rissanen P, Lindgren KA, Sarna S, Hurri H. A randomized trial of combined manipulation, stabilizing exercises, and physician consultation compared to physician consultation alone for chronic low back pain. Spine (Phila Pa 1976).Oct 1 2003; 28(19):2185-2191.
48.Burton AK, Tillotson KM, Cleary J. Single-blind randomised controlled trial of chemonucleolysis and manipulation in the treatment of symptomatic lumbar disc herniation. Eur Spine J. Jun 2000; 9(3):202-207.
Mixed diagnoses used in analyses and not listed in Tables as acute and chronic pain
49. Beyerman KL, Palmerino MB, Zohn LE, Kane GM, Foster KA. Efficacy of treating low back pain and dysfunction secondary to osteoarthritis: chiropractic care compared with moist heat alone. J Manipulative PhysiolTher. Feb 2006; 29(2):107-114.
50. Bronfort G. Chiropractic versus general medical treatment of low back pain: a small scale controlled clinical trial. Am J Chiropractic Med. 1989; 2:145-150.
51. Doran DM, Newell DJ. Manipulation in treatment of low back pain: a multicentre study. Br Med J. Apr 26 1975; 2(5964):161-164.
52.Hawk C, Long CR, Rowell RM, Gudavalli MR, Jedlicka J. A randomized trial investigating a chiropractic manual placebo: a novel design using standardized forces in the delivery of active and control treatments. J Altern Complement Med. Feb 2005; 11(1):109-117.
53.Hurwitz EL, Morgenstern H, Harber P, et al. A randomized trial of medical care with and without physical therapy and chiropractic care with and without physical modalities for patients with low back pain: 6-month follow-up outcomes from the UCLA low back pain study. Spine. Oct 15 2002; 27(20):2193-2204.
54.Meade TW, Dyer S, Browne W, Frank AO. Randomised comparison of chiropractic and hospital outpatient management for low back pain: results from extended follow up. BMJ. Aug 5 1995; 311(7001):349-351.
55.Sims-Williams H, Jayson MI, Young SM, Baddeley H, Collins E. Controlled trial of mobilisation and manipulation for patients with low back pain in general practice. Br Med J. Nov 11 1978; 2(6148):1338-1340.
56.Sims-Williams H, Jayson MI, Young SM, Baddeley H, Collins E. Controlled trial of mobilisation and manipulation for low back pain: hospital patients. Br Med J. Nov 24 1979; 2(6201):1318-1320.