Indications for administration of parenteral nutrition in adults

Nutrition in Clinical Practice

Volumn 19, Issue 3, 2004, Pages 255-262

  Braunschweig, Carol ^a   Liang, HuiFang ^a   Sheean, Patricia ^a  

^a UNIVERSITY OF ILLINOIS AT CHICAGO   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

CLINICAL PROTOCOL; CLINICAL TRIAL; CONTROLLED CLINICAL TRIAL; ESOPHAGUS CANCER; HUMAN; INFECTION CONTROL; MALNUTRITION; MEDICAL LITERATURE; META ANALYSIS; MORTALITY; NUTRITIONAL SUPPORT; OUTCOMES RESEARCH; PARENTERAL NUTRITION; PATIENT CARE; POPULATION RESEARCH; POSTOPERATIVE COMPLICATION; PROSPECTIVE STUDY; PUBLICATION; RANDOMIZED CONTROLLED TRIAL; REVIEW; RISK BENEFIT ANALYSIS; STOMACH CANCER; SYSTEMATIC REVIEW; TREATMENT INDICATION;

EID: 2942562030     PISSN: 08845336     EISSN: None     Source Type: Journal    
DOI: 10.1177/0115426504019003255     Document Type: Review

References (120)

1. Abel RM, Fischer JE, Buckley MJ, Barnett GO, Austen G. Malnutrition in cardiac surgical patients. Arch Surg. 1976;111:45-50.
2. Askanazi J, Starker PM, Olsson C, et al. Effect of immediate postoperative nutritional support on length of hospitalization. Ann Surg. 1986;203:236-239.
3. Bellantone R, Doglietto GB, Bossola M, Pacelli F, Negro F, Crucitti F. Preoperative parenteral nutrition in malnourished high-risk surgical patients. Nutrition. 1990;6:168-170.
4. Bellantone R, Doglietto GB, Bossola M, et al. Preoperative parenteral nutrition of malnourished surgical patients. Acta Chir Scand. 1988;22:249-251.
5. Bellantone R, Doglietto GB, Bossola M, et al. Preoperative parenteral nutrition in the high-risk surgical patient. JPEN. 1988;12:195-197.
6. Black DD, Suttle EA, Whitington PF, Whitington GL, Korones SD. The effect of short-term total parenteral nutrition (TPN) on hepatic function in the human neonate: a prospective randomized study demonstrating alteration of hepatic canalicular function. J Pediatr. 1981;99:445-449.
7. Bonau RA, Ang SD, Jeevanandam M, Daly JM. High branched-chain amino acid solutions: relationship of composition to efficacy. JPEN. 1984;8:622-627.
8. Brans YW, Sumners JE, Dweck HS, Cassady G. Feeding the low birth weight infant: orally or parenterally? preliminary results of a comparative study. Pediatrics. 1974;54:15-22.
9. Brennan MF, Pisters PW, Posner M, Quesada O, Shike M. A prospective randomized trial of TPN after major pancreatic resection for malignancy. Ann Surg. 1994;220:436-444.
10. Buzby GP, Knox LS, Crosby LO, et al. Study protocol: a randomized clinical trial of TPN in malnourished surgical patients. Am J Clin Nutr. 1988;47:366-381.
11. Buzby GP, Williford WO, Peterson OL, et al. A randomized clinical trial of TPN in malnourished surgical patients: the rationale and impact of previous clinical trials and pilot study on protocol design. Am J Clin Nutr. 1988;47:357-365.
12. Capella G, Ruiz JM, Hidalgo L, Alonso M, Salvador R, Cardona D. Valor de la nutricion parenteral en la gastrectomia total porcancer: estudio prospectivo. Nutr Hosp. 1990;5:317-321.
13. Cardona D, Del Moral V, Salvador R, Andreu MA, Trias R, Bonal J. Early postoperative TPN in gastric cancer: a cost-effectiveness study. J Clin Nutr Gastroenterol. 1986;1:267-270.
14. Charash WE, Kearney PA, Annie KA, et al. Early enteral feeding is associated with an attenuation of the acute phase/cytokine response and improved outcome following multiple trauma [Abstract]. J Trauma. 1994;37:1015.
15. Charuhas PM, Fosberg KL, Bruemmer B, et al. A double-blind randomized trial comparing outpatient parenteral nutrition with intravenous hydration: effect of resumption of oral intake after marrow transplantation. JPEN. 1997;21:157-161.
16. Chiarelli AG, Ferrarello S, Piccioli A, et al. La nutrizione enterale totale verso la nutrizione mista enterale e parenterale in pazienti ricoverati in una terapia intensiva polivalente. Minerva Anestesiol. 1996;62:1-7.
17. Clamon GH, Feld R, Evans WK, et al. Effect of adjuvant central IV hyperalimentation on the survival and response to treatment of patients with small cell lung cancer: a randomized trial. Cancer Treat Rep. 1985;69:167-177.
18. Coquin JY, Maraninchi D, Gastaut JA, Carcassonne Y. Influence of parenteral nutrition (PN) on chemotherapy and survival of acute leukemias (AL): preliminary results of a randomized trial. JPEN. 1981;5:357.
19. Coquin JY, Maraninchi D, Gastaut JA, Carcassonne Y. Parenteral nutrition in chemotherapy of acute leukemias: preliminary results. JPEN. 1980;4:437.
20. Cromack D, Moley J, Pass H, et al. Prospective randomized trial of parenteral nutrition (TPN) compared to ad lib oral nutrition (ON) in patients with upper GI cancer and weight loss undergoing surgical treatment. Program of the 22nd Annual Meeting of the Association for Academic Surgery, 1988:86.
21. DeCicco M, Panarello G, Fantin D, et al. Parenteral nutrition in cancer patients receiving chemotherapy: effects of toxicity and nutritional status. JPEN. 1993;17:513-518.
22. Dickinson RJ, Ashton MG, Axon ATR, Smith RC, Yeung CK, Hill GL. Controlled trial of intravenous hyperalimentation and total bowel rest as an adjunct to the routine therapy of acute colitis. Gastroenterology. 1980;79:1199-1204.
23. Doglietto GB, Gallitelli L, Pacelli F, et al. Protein-sparing therapy after major abdominal surgery: lack of clinical effects: Protein-Sparing Therapy Study Group. Ann Surg. 1996;223:357-362.
24. Donaldson SS, Wesley MN, Ghavimi F, Shils ME, Suskind RM, DeWys WD. A prospective randomized clinical trial of TPN in children with cancer. Med Pediatr Oncol. 1982;10:129-139.
25. Drott C, Unsgaard B, Schersten T, Lundholm K. TPN as an adjuvant to patients undergoing chemotherapy for testicular carcinoma: protection of body composition: a randomized, prospective study. Surgery. 1988;103:499-506.
26. Eisenberg JM, Glick HA, Buzby GP, Kinosian B, Williford WO. Does perioperative TPN reduce medical care costs? JPEN. 1993;17:201-209.
27. Evans WK, Makuch R, Clamon GH, et al. Limited impact of TPN on nutritional status during treatment for small cell lung cancer. Cancer Res. 1985;45:3347-3353.
28. Fan ST, Lau WY, Wong KK, Chan YPM. Pre-operative parenteral nutrition in patients with oesophageal cancer: a prospective, randomised clinical trial. Clin Nutr. 1989;8:23-27.
29. Fan S-T, Lo C-M, Lai ECS, Chu K-M, Liu C-L, Wong J. Perioperative nutritional support in patients undergoing hepatectomy for hepatocellular carcinoma. N Engl J Med. 1994;331:1547-1552.
30. Figueras J, Puig P, Rafecas A, et al. Postoperative hypocaloric parenteral nutrition. Acta Chir Scand. 1988;154:435-438.
31. Freund H, Hoover HC, Atamian S, Fischer JE. Infusion of the branched-chain amino acids in postoperative patients. Ann Surg. 1979;190:18-23.
32. Garden OJ, Smith A, Harris NWS, Shenkin A, Sim AJW, Carter DC. The effect of isotonic amino acid infusions on serum proteins and muscle breakdown following surgery. Br J Surg. 1983;70:79-82.
33. Ghavimi F, Shils ME, Scott BF, Brown M, Tamaroff M. Comparison of morbidity in children requiring abdominal radiation and chemotherapy, with and without TPN. J Pediatr. 1982;101:530-537.
34. Gunn T, Reaman G, Outerbridge EW, Colle E. Peripheral TPN for premature infants with the respiratory distress syndrome: a controlled study. J Pediatr. 1978;92:608-613.
35. Gys T, Peeters R, Hubens A. The value of short-term peripheral parenteral nutrition after colorectal surgery: a comparative study with conventional postoperative intravenous fluid. Acta Chir Belg. 1990;90:234-239.
36. Hansell DT, Davies JWL, Shenkin A, Garden OJ, Burns HJG, Carter DC. The effects of an anabolic steroid and peripherally administered intravenous nutrition in the early postoperative period. JPEN. 1989;13:349-358.
37. Hays DM, Merritt RJ, White L, Ashley J, Siegel SE. Effect of TPN on marrow recovery during induction therapy for acute nonlymphocytic leukemia in childhood. Med Pediatr Oncol. 1983;11:134-140.
38. Heim ME. Adjuvante parenterale ernahrung bei zytostatischer chemotherapie. Infusionstherapie. 1986;13:115-121.
39. Herndon DN, Barrow RE, Stein M, et al. Increased mortality with intravenous supplemental feeding in severely burned patients. J Burn Care Rehabil. 1989;10:309-313.
40. Hickey AJ, Toth BB, Lindquist SB. Effect of intravenous hyperalimentation and oral care on the development of oral stomatitis during cancer chemotherapy. J Prosthet Dent. 1982;47:188-193.
41. Hoffmann E, Hansen BB, Owen-Falkenberg T, Djorup J. Total parenteral ernaering ved colonkirurgi. Ugeskr Laeger. 1988;150:1277-1279.
42. Hogbin BM, Smith AM, Craven AH. An evaluation of peripheral essential amino acid infusion following major surgery. JPEN. 1984;8:511-514.
43. Holter AR, Fischer JE. The effects of perioperative hyperalimentation on complications in patients with carcinoma and weight loss. J Surg Res. 1977;23:31-34.
44. Hu SS, Fontaine F, Kelly B, Bradford DS. Nutritional depletion in staged spinal reconstructive surgery. Spine. 1998;23:1401-1405.
45. Hwang T-L, Mou S-C, Chen M-F. The importance of a source of sufficient protein in postoperative hypocaloric partial parenteral nutrition support. JPEN. 1993;17:254-256.
46. Hyde D, Floch MH. The effect of peripheral nutritional support and nitrogen balance in acute pancreatitis. Gastroenterology. 1984;86:1119.
47. Hyltander A, Drott C, Unsgaard B, et al. The effect on body composition and exercise performance of home parenteral nutrition when given as adjunct to chemotherapy of testicular carcinoma. Eur J Clin Invest. 1991;21:413-420.
48. Issell BF, Valdivieso M, Zaren HA, et al. Protection against chemotherapy toxicity by IV hyperalimentation. Cancer Treat Rep. 1978;62:1139-1143.
49. Jensen S, Ginnerup P. Total parenteral ernaering perioperativt til patienter med adenocarcinoma recti. Ugeskr Laeger. 1982;144:460-463.
50. Jensen S. Clinical effects of enteral and parenteral nutrition preceding cancer surgery. Med Oncol Tumor Pharmacother. 1985;2:225-229.
51. Jensen S. Parenteral nutrition and cancer surgery [Abstract]. JPEN. 1982;6:335.
52. Jimenez Jimenez FJ, Ortiz Leyba C, Jimenez Jimenez LM, Garcia Valdecasas MS, Garnacho Montero J. Study of hypocaloric peripheral parenteral nutrition in postoperative patients (European Project). Clin Nutr. 1995;14:88-96.
53. Jin D, Phillips M, Byles JE. Effects of parenteral nutrition support and chemotherapy on the phasic composition of tumor cells in gastrointestinal cancer. JPEN. 1999;23:237-241.
54. Jordan WM, Valdivieso M, Frankmann C, et al. Treatment of advanced adenocarcinoma of the lung with Ftorafur, doxorubicin, cyclophosphamide, and cisplatin (FACP) and intensive iv hyperalimentation. Cancer Treat Rep. 1981;65:197-205.
55. Kinsella TJ, Malcolm AW, Bothe A, Valerio D, Blackburn GL. Prospective study of nutritional support during pelvic irradiation. Int J Radiat Oncol Biol Phys. 1981;7:543-548.
56. Kirvela O, Stern RC, Askanazi J, Doershuk CF, Rothkopf MM, Katz DP. Long-term parenteral nutrition in cystic fibrosis. Nutrition. 1993;9:119-126.
57. Lanzotti V, Copeland E, Bhuchar V, Wesley M, Orriere J, Dudrick S. Randomized trial of TPN with chemotherapy for non-oat cell lung cancer (NOCLC) [Abstract]. Proc AACR ASCO. 1980;21:377.
58. Levine AS, Brennan MF, Ramu A, Fisher RI, Pizzo PA, Glaubiger DL. Controlled clinical trials of nutritional intervention as an adjunct to chemotherapy, with a comment on nutrition and drug resistance. Cancer Res. 1982;(suppl)42:774s-781s.
59. Lorenzoni K. Postoperative infusions therapie in der abdominal-chirurgie. Wien Mediz Wochenschr. 1981;131:485-491.
60. Lough M, Watkins R, Campbell M, Carr K, Burnett A, Shenkin A. Parenteral nutrition in bone marrow transplantation. Clin Nutr. 1990;9:97-101.
61. Marin VB, Rebollo MGJ, Castillo-Duran CD, et al. Controlled study of early postoperative parenteral nutrition in children. J Pediatr Surg. 1999;34:1330-1335.
62. Mattioli S, Lassari A, Lerro F, et al. Nutrizione parenterale totale dopo interventi di chirurgia digestiva maggiore. Chirurgia. 1993;6:129-133.
63. McIntyre PB, Powell-Tuck J, Wood SR, et al. Controlled trial of bowel rest in the treatment of severe acute colitis. Gut. 1986;27:481-485.
64. Meguid MM, Curtas MS, Meguid V, Campos AC. Effects of pre-operative TPN on surgical risk: preliminary status report. Br J Clin Pract. 1988;(Suppl 63):53-58.
65. Melchior J-C, Chastang C, Gelas P, et al. Efficacy of 2-month TPN in AIDS patients: a controlled randomized prospective trial. AIDS. 1996;10:379-384.
66. Melchior J-C, Gelas P, Carbonnet F, et al. Improved survival by home TPN in AIDS patients: follow-up of a controlled randomized prospective trial. AIDS. 1998;12:336-337.
67. Muller JM, Brenner U, Dienst C, Pichlmaier H. Preoperative parenteral feeding in patients with gastrointestinal carcinoma. Lancet. 1982;1:68-71.
68. Muller JM, Keller HW, Brenner U, Walter M, Holzmuller W. Indications and effects of preoperative parenteral nutrition. World J Surg. 1986;10:53-63.
69. Muller JM, Thul P, Halber M, Huber P. Parenteral nutrition in tumor patients. Recent Results Cancer Res. 1988;108:185-193.
70. Naveau S, Pelletier G, Poynard T, et al. A randomized clinical trial of supplementary parenteral nutrition in jaundiced alcoholic cirrhotic patients. Hepatology. 1986;6:270-274.
71. Neuvonen P, Salo M. Effects of preoperative parenteral nutrition on cell-mediated immunity in malnourished patients. Clin Nutr. 1984;3:197-201.
72. Nixon DW, Heymsfield SB, Lawson DH, et al. Effect of TPN on survival in advanced colon cancer. Cancer Detect Prev. 1981;4:421-427.
73. Nixon DW, Moffitt S, Lawson DH, et al. TPN as an adjunct to chemotherapy of metastatic colorectal cancer. Cancer Treat Rep. 1981;65(Suppl 5):121-128.
74. O'Mahony JB, McIrvine AJ, Palder SB, et al. The effect of short-term postoperative intravenous feeding upon cell-mediated immunity and serum suppressive activity in well-nourished patients. Surg Gynecol Obstet. 1984;159:27-32.
75. Pildes RS, Ramamurthy RS, Cordero GV, Wong PWK. Intravenous supplementation of l-amino acids and dextrose in low-birth-weight infants. J Pediatr. 1973;82:945-950.
76. Popp MB, Fisher RI, Simon RM, Brennan MF. A prospective randomized study of adjuvant parenteral nutrition in the treatment of diffuse lymphoma: effect on drug tolerance. Cancer Treat Rep. 1981;65(Suppl 5):129-135.
77. Popp MB, Fisher RI, Wesley R, Aamodt R, Brennan MF. A prospective randomized study of adjuvant parenteral nutrition in the treatment of advanced diffuse lymphoma: influence on survival. Surgery. 1981;90:195-203.
78. Reilly J, Mehta R, Teperman L, et al. Nutritional support after liver transplantation: a randomized prospective study. JPEN. 1990;14:386-391.
79. Rimbau V, Cardona D, Escudero JR, Artega R, Mestres JM, Viver E. Efecto de la nutricion parenteral periferica en el postoperatorio inmediato de la cirugia del sector aortico. Angiologia. 1989;41:87-91.
80. Roberts S, Miller JE, Pineiro LA. Is TPN beneficial in breast cancer patients after autologous marrow or blood transplantation? JPEN. 2000;24:S11-S12.
81. Russell DM, Shike M, Marliss EB, et al. Effects of TPN and chemotherapy on the metabolic derangements in small cell lung cancer. Cancer Res. 1984;44:1706-1711.
82. Samuels ML, Selig DE, Ogden S, Grant C, Brown B. IV hyperalimentation and chemotherapy for stage III testicular cancer: a randomized study. Cancer Treat Rep. 1981;65:615-627.
83. Sandstrom R, Drott C, Hyltander A, et al. The effect of postoperative intravenous feeding (TPN) on outcome following major surgery evaluated in a randomized study. Ann Surg. 993;217:185-195.
84. Sax HC, Warner BW, Talamini MA, et al. Early TPN in acute pancreatitis: lack of beneficial effects. Am J Surg. 1987;153:117-124.
85. Serrou B, Cupissol D, Plagne R, Boutin P, Carcassone Y, Michel FB. Parenteral intravenous nutrition (PIVN) as an adjunct to chemotherapy in small cell anaplastic lung carcinoma. Cancer Treat Rep. 1981;65(Suppl 5):151-155.
86. Serrou B, Cupissol D, Plagne R, et al. Follow-up of a randomized trial for oat cell carcinoma evaluating the efficacy of peripheral intravenous nutrition (PIVN) as adjunct treatment. Recent Results Cancer Res. 1982;80:246-253.
87. Serrou B, Cupissol D, Rey A, et al. La nutrition parenterale en tant qu'adjuvant therapeutique: resultats a 30 mois d'un essai randomise pour les malades porteurs de cancers anaplasiques des bronches. Bull Cancer. 1983;70:84-87.
88. Shamberger RC, Brennan MF, Goodgame JT, et al. A prospective, randomized study of adjuvant parenteral nutrition in the treatment of sarcomas: results of metabolic and survival studies. Surgery. 1984;96:1-12.
89. Shamberger RC, Pizzo PA, Goodgame JT, et al. The effect of TPN on chemotherapy-induced myelosuppression. Am J Med. 1983;74:40-48.
90. Shike M, Feld R, Evans WK, Shepherd FA, Harrison JE, Jeejeebhoy KN. Long-term effect of TPN on body composition of patients with lung carcinoma [Abstract]. JPEN. 1981;5:564.
91. Shike M, Russell DM, Detsky AS, et al. Changes in body composition in patients with small-cell lung cancer. Ann Intern Med. 1984;101:303-309.
92. Simms JM, Oliver E, Smith JAR. A study of TPN in major gastric and esophageal resection for neoplasia [Abstract]. JPEN. 1980;4:422.
93. Simon D, Galambos JT. A randomized controlled study of peripheral parenteral nutrition in moderate and severe alcoholic hepatitis. J Hepatol. 1988;7:200-207.
94. Smith RC, Hartemink R. Improvement of nutritional measures during preoperative parenteral nutrition in patients selected by the prognostic nutritional index: a randomized controlled trial. JPEN. 1988;12:587-591.
95. Solassol C, Joyeaux H, Dubois JB. TPN with complete nutritive mixtures: an artificial gut in cancer patients. Nutr Cancer. 1979;1:13-18.
96. Solassol C, Joyeux H. Artificial gut with complete nutritive mixtures as a major adjuvant therapy in cancer patients. Acta Chir Scand. 1979;(Suppl 494):186-188.
97. Song Y, Kang X, Xia X, Shi Y, Sun Z. Clinical observation of short-term nutritional support in treatment of advanced COPD. Chin J Intern Med (Chung Hua Nei Ko Tsa Chih). 1993;32:819-822.
98. The Veterans Affairs Total Parenteral Nutrition Cooperative Study Group. Perioperative TPN in surgical patients. N Engl J Med. 1991;325:525-532.
99. Thompson BR, Julian TB, Stremple JF. Perioperative TPN in patients with gastrointestinal cancer. J Surg Res. 1981;30:497-500.
100. Vaidya UV, Bhave SA, Pandit AN. Parenteral nutrition (PN) in the management of very low birthweight (VLBW) babies: a randomized controlled trial. Indian Pediatr. 1995;32:165-170.
101. Valdivieso M, Bodey GP, Benjamin RS, et al. Role of intravenous hyperalimentation as an adjunct to intensive chemotherapy for small cell bronchogenic carcinoma. Cancer Treat Rep. 1981;65(Suppl 5):145-150.
102. Valdivieso M, Frankmann C, Murphy WK, et al. Long-term effects of intravenous hyperalimentation administered during intensive chemotherapy for small cell bronchogenic carcinoma. Cancer. 1987;59:362-369.
103. Valerio D, Overett L, Malcolm A, Blackburn GL. Nutritional support for cancer patients receiving abdominal and pelvic radiotherapy: a randomized prospective clinical experiment of intravenous versus oral feeding. Surg Forum. 1978;29:145-149.
104. Van Eys J, Copeland EM, Cangir A, et al. A clinical trial of hyperalimentation in children with metastatic malignancies. Med Pediatr Oncol. 1980;8:63-73.
105. Van Eys J, Wesley MN, Cangir A, et al. Safety of intravenous hyperalimentation in children with malignancies: a cooperative group trial. JPEN. 1982;6:291-294.
106. Von Meyenfeldt MF, Meijerink WJHJ, Rouflart MMJ, Builmaassen MTHJ, Soeters PB. Perioperative nutritional support: a randomized clinical trial. Clin Nutr. 1992;11:180-186.
107. Weiner RS, Kramer BS, Clamon GH, et al. Effects of intravenous hyperalimentation during treatment in patients with small-cell lung cancer. J Clin Oncol. 1985;3:949-957.
108. Weisdorf S, Lysne J, Wind D, et al. Influence of prophylactic TPN on long-term outcome of bone marrow transplantation (BMT). JPEN. 1986;10:5S.
109. Weisdorf SA, Lysne J, Wind D, et al. Positive effect of prophylactic TPN on long-term outcome of bone marrow transplantation. Transplantation. 1987;43:833-838.
110. Williford WO, Krol WF, Buzby GP. Comparison of eligible randomized patients with two groups of ineligible patients: can the results of the VA TPN clinical trial be generalized? J Clin Epidemiol. 1993;46:1025-1034.
111. Woolfson AM, Smith JA. Elective nutritional support after major surgery: a prospective randomized trial. Clin Nutr. 1989;8:15-21.
112. Wu C-W, Meng HC, Mok K-T, et al. Effect of TPN on the postoperative outcome in aged patients with gastric cancer. Dig Surg. 1995;12:164-170.
113. Yamada N, Koyama H, Hioki K, Yamada T, Yamamoto M. Effect of postoperative TPN as an adjunct to gastrectomy for advanced gastric carcinoma. Br J Surg. 1983;70:267-274.
114. Heyland DK, MacDonald S, Keefe L, Drover JW. TPN in the critically ill: a meta-analysis. JAMA. 1998;280:2013-2019.
115. Heyland DK, Montalvo M, MacDonalk S, et al. TPN in the surgical patient: a meta-analysis. Can J Surg. 2001;44:102-111.
116. Braunschweig C, Levy P, Sheean P, Wang X. Enteral versus parenteral nutrition: a meta-analysis. Am J Clin Nutr. 2001;74:534-542.
117. American Gastroenterological Association Clinical Practice and Practice Economics Committee. AGA technical review on parenteral nutrition. Gastroenterology. 2001;121:970-1001.
118. nd ed. Oxford, United Kingdom: Oxford University Press; 2000:265-271.
119. McAlister FA, Clark HD, van Walraven C, et al. The medical review article revisited: has the science improved? Ann Intern Med. 1999;131:947-951.
120. Koretz RL. Methods of meta-analysis: an analysis. Curr Opin Clin Nutr Metab Care. 2002;5:467-474.