OBJECTIVES OF THE STUDY

• To realize a systematic revision of the Literature published on the consumption of beer and its possible effects on the human health in the period of time between 1998 and May of 2000.
• To group all these vital revisions by different groups from pathologies or situations to be able to simplify its search on the part of investigators in the subject.
• To analyze the possibility of applying to techniques used in studies epidemiologists, considering the put-analysis like more important element.
• To raise future lines of investigation on the subject and the possible prospective studies that they give applicable information us for the human health.

INTRODUCTION

The put-analysis is a relatively new scientific discipline, that consists basically of combining data of several studies and that can be defined of different ways.

Glass was first that, in 1976, proposed the term “put-analysis” to differentiate it from “overviews” which they are merely narrative revisions (Glass, 1976). 1985 can be considered that this type of analysis consists of the use of the results of diverse studies to answer a specific question, generally of quantitative way (Louis, Finenberg and Mosteller,). It tries to analyze and to synthesize independent studies that turn on a same subject (Jenicek, 1996).

The put-analysis is a set of different statistical techniques, whose objective is to make a qualitative and quantitative synthesis of the results of the different independent studies, that they deal with a same subject (Hunter, Schmidt and Jacson, 1987).

Rarely an isolated study can contribute a definitive solution to a problem. For a long time, it is accepted that the scientific advance is obtained with the accumulation of the results coming from diverse studies, results that can be discordant (Horwitz, 1979; Horwitz, 1987).

In order to solve these discrepancies, one has resorted classically to the revisions, focused of narrative and nonsystematic form. This process characterized by the lack of you rule of action is often subjective (for example usually one does not consider the sample size, the magnitude of the effect, the design of the studies). The put-analysis is the attempt to surpass these limitations and therefore it must be considered complementary and nonopposite to the narrative revision (Fernandez-Ballart, Vobecky and Marti-Henneberg, 1991). It represents a more explicit advantage of the revision of Literature.

Between the utilities of the put-analysis they emphasize:

• Combination of studies with a so large reduced population sample/with the intention of obtaining trustworthy answers (Dominguez and cabbages., 1990).
• When unfinished studies exist, its combination with others can lead to a valid answer (Sacks, Berrier and Reitman, 1987; Gerbarg and Horwitz, 1988).
• To obtain conclusions when the results are contradictory
• To respond to questions nonposed in the original studies.

Also he is interesting to indicate that the last objective of all revision is to contribute suggestions. This objective is not covered solely saying “that more studies are necessary” but also he is interesting to indicate the activities that seem more fruitful. (Fernandez-Ballart, Vobecky and Martí-Henneberg, 1991)

The put-analysis, like summary, presents/displays a series of advantages and disadvantages that we indicated:

Advantages

The statistical methodology that is applied to the data of the studies combined in an put-analysis, increases the statistical power of the same. In the accomplishment of this analysis they are reviewed, always with critical spirit for the sake of the validity of the final result, numerous studies reason why are increased and the information regarding a subject is selected in particular.

Disadvantages

The put-analysis is realized generally retrospectively, although also it is possible to carry out it of prospective form. This can present/display a problem regarding the obtaining of the necessary data for its accomplishment, because explicitly they are not indicated in the original work. Although this problem can be tried to solve putting itself in contact with the authors (who generally facilitate the required information), is something that complica and delays a process that of in case he is already complex and long (Dominguez and cabbages., 1990)

However, the main disadvantage is the heterogeneity of the works that are going away to combine, being the most important causes the slants, as much of sampling, as in the interpretation of the results or the publication (Kleinbaum, Kupper and Morgensten, 1982 a; Kleinmaum, Kupper and Morgensten, 1982 b; Kleinbaum, Kupper and Morgensten, 1982 cs; Chalmers, Celano and Sacks, 1983; Smith, 1980; Rosenthal, 1979; Begg and Berlin, 1989)

Part of these problems is resolved putting under the different selected works from a rigorous examination of quality that is realized completely without information and by several investigators (Chalmers, Smith and Blackburn, 1981)

Also he is interesting to count on the amplest phantom of valid works and quality that we are able to compile, whether are concordant as if they are not it (Tacker, 1988). In theory, all the eligible studies would have to be including avoiding slanted systematic in their selection (Glass, McGraw and Smith, 1984)

Another disadvantage it can represent including works only published, since we can incur a slant in favor of the significant results and to the detriment of the negative results (Chan, Sacks and Chalmers, 1982; Koren and cabbages. 1989; Dickersin, 1990). Since the prevention of slanted saying not always is possible (Sharp, 1990), it is possible to be tried to quantify his importance. Between different methods proposed for it (Simes, 1987; Begg, 1985), one of simplest and used consist of calculating the number of published studies (of half null effect) necessary not to turn into nonsignificant the difference of effect found with the published studies put-analyzed (Rosenthal, 1979; Einarson and cabbages, 1985).

The conclusion of an put-analysis is so much more solid whichever major is the number of not published negative studies necessary to refute it (Fernandez-Ballart, Vobecky and Marti-Henneberg, 1991).

PROCEDURE

In the first place it is come to realize the search and compilation of the bibliography. For it, the data bases by access are consulted “on line”. This system presents/displays a series of advantages and disadvantages. Between the advantages they are: the one that the information is obtained quickly; the search is ample, since the files in which we looked for are extensive; bench mark is obtained to major generally that the obtained ones in the classic search. With respect to the disadvantages, we mentioned: the one that the stored information is not very antigüa; all the matters are not contained in the data bases; they provide references, which does not mean that they have the primary document (original work of the investigation) that, in addition, in a great percentage they are articles of magazines that later there are to locate (It gives Costa and Fontecilla, 1993).

The data bases that we have consulted are MEDLINE, EMBASE and TOXLINE

Within the most important field of the Medicine they are MEDLINE and EMBASE (It gives Costa and Fontecilla, 1993).

* MEDLINE (Hewitt and Chalmers, 1985 a; Hewitt and Chalmers, 1985 b; Haynes, McKibbon and Walker, 1985; Dickersin, Hewitt and Mutch, 1985; Poynard and Cohn, 1985) produced by the National Library of Medicine, is one of most complete. It includes article references of 3200 magazines, published in near 70 countries.

* EMBASE, produced by Medical Excerpta (Foundation Elsevier Medical Excerpta of Amsterdam) compiles the references of 3500 periodic publications (magazines are included and a great number of monographs, doctoral theses, acts of congresses, etc.) of about 100 countries. In relation to the thematic one that approaches, she is more complete than Medline.

* TOXLINE, elaborated by the National Library of Medicine, is a base of data of Toxicology (It gives Costa and Fontecilla, 1993). It includes articles of magazines, monographs, acts of congresses, etc.

As key word is used “to beer”, limiting the period of time between January of 1998 and May of 2000. A total of 403 referenced works is obtained.

A first analysis of these references takes to us to eliminate those that directly do not talk about to the beer and the human health, in particular 113 and that is fitted within the following aspects:

• Not related to the beer (70) (when using “to beer” like key word, they appear referring works to the Law of Lambert Beer, etc.).
• Other that although are related to the beer, are regarding microbiological biotechnology and technical of fermentation, in their great majority (43).

Therefore, the bench mark that later is reviewed is 291 (another reference is included that is located from the bibliography).

With respect to the date of publication, the rank is 1993-2000 (Table 1). The 1995 publication is the one that is located from the bibliography. Approximately, 87% were published in 1998 and 1999 and of this year there are 29 works.

Table 1. - Distribution per year of publication
Year	publication	Number %
1993	2	0.69
1995	1	0.34
1996	1	0.34
1997	5	1.72
1998	133	45.70
1999	120	41.24
2000	29	9.96

As our general mission is ample, to determine the effects of the beer consumption on the human health, the selection criteria that pay attention initially are not too restrictive:

• Original works/revisions
• Consumption of beer and effects on the health
• In humans

First selection

The application of the mentioned criteria takes to us to reject, in the first place 57 articles, which supposes a 19% approximately, being the reasons of this rejection those that they are mentioned next (Table 2):

• Hlywka JJ, Bullerman LB. Ocurrence of fumonisin B1 and B2 in beer. Food Addit Contam 1999, 16 (8): 319-24.
• Herce-Paglial C, Gonzalez G, Camean A.M., Repetto M. arsenical Presence and distribution of species in beers. Food Addit Contam 1999, 16 (6): 267-71.
• Whiting MS, Ingledew WM, Lee SY, Bacterial Ziola B. surface antigen-specific monoclonal antibodies used to detect to beer spoilage pediococci. Dog J Microbiol 1999, 45 (10): 670-7.
• Chen YC, Hu A. Simultaneous determination of draws up benzodiazepines from drinks by using direct electrospray probe/mass spectrometry (DEP/MS). Forensic Sci Int 1999, 103 (2): 79-88.
• Ekundayo EO, Obuekwe CO. The relationship between soil to copper content and to copper resistance in yeast of an ultisol in midwestern Nigeria. Plant Foods Hum Nutr 1999, 53 (2): 175-81.
• Nakajima M, Tsubouchi H and Miyabe M. To survey of ochratoxin To and aflatoxins in domestic and imported beers in Japan by inmunoaffinity and liquid chromatography. J AOAC Int 1999, 84 (4): 897-902.
• Chihib NE, Tholozan JL. Effect of rapid cooling and acidic pH on to cellular homeostasis of Pectinatus frisingensis, to strictly anaerobic beer-spoilage bacterium. Int J Food Microbiol 1999, 48 (3): 191-202.
• Schroder J. Probing plant polyketide biosynthesis. Nat Struct Biol 1999, 6 (8): 714-6.
• Shayo NB, Nnko SA, Gidamis AB, Dillon VM. Assessment of cyanogenic glucoside (cyanide) residues in Mbege: an opaque traditional Tanzanian beer. Int J Food Sci Nutr 1998, 49 (5): 333-8.
• They go Hamersveld EH, they go to der Lans RG, Caulet PJ, Luyben KC. Modeling brewers´ yeast flocculation. Biotechnol Bioeng 1998, 57 (3): 330-41.
• Jin D, Miyahara T, Oe T, Toyo´oka D-amino T.Determination of acids labeled with fluorescent chiral reagents, R (-) and S (+) - 4 (3-isothiocyanatopyrrolidin-1-yl) - 7 (N, N-dimethylaminosulfonyl) - 2,1,3-benzoxadiazoles, in biological and food samples by liquid chromatography. Anal Biochem 1999, 269 (1): 124-32.
• Stevens JF, Taylor AW, Deinzer ML Quantitative analysis of xanthohumol and related prenylflavonoids in hops and to beer by liquid chromatography-tandem mass spectrometry. J Chromatogr To 1999, 832 (1-2): 97-107.
• Katia J, Trugo LC. Quality control of to beer hopped with reduced isomerized products. Arch Latinoam Nutr 1988, 48 (3): 242-6
• Intranuovo LR, Powers AS. The perceived bitterness of to beer and 6-n-propylthiouracil (PROP) taste sensitivity. Ann N and Acad Sci 1998, 30 (855): 813-5
• Tawfik MS, Huyghebaert A. Polystyrene cups and containers: styrene migration. Food Addit Contam 1998, 15 (5): 592-9
• Toko K. Electronic tongue. Biosens Bioelectron 1998.13 (6): 701-9
• they go to der Aa Kuhle To, Jespersen L. Detection and identification of wild yeast in lager breweries. Int J Food Microbiol 1998, 43 (3): 205-13
• Lopez FF, Goatherd C, Lorenzo ML, Lopez MC. Aluminum levels in wine, to beer and to other alcoholic beverages consumed in Spain. Total Sci Environ 1998, 220 (1): 1-9
• Lendinez and, Lopez MC, Goatherd C, Lorenzo ML Determination of chromium in wine and to other alcoholic beverages consumed in electrothermal Spain by atomic absorption spectrometry. J AOAC Int 1998 81 (5): 1043-7
• Chappel CI, Smith SY, Chagnon M. Subchronic toxicity study of tetrahydroisohumulone and hexahydroisohumulone in the beagle dog. Food Chem Toxicol 1998 36 (11): 915-22
• Pimenta MJ, Kaneta T, Larondelle and, Dohmae N, Kamiya and. S-adenosyl-L-methionine: L-methionine S-methyltransferase from germinating barley. Purification and localization. Plant Physiol 1998, 118 (2): 431-8
• Vinogradov and, Beer mug K. Structural determination of some new oligosaccharides and analysis of the branching pattern of isomaltooligosaccharides from to beer. Carbohydr Head of cattle 1998, 309 (1): 57-64
• Timmins member state, Quain OF, Gooddacre R. Differentiation of brewing yeast strains by pyrolysis mass spectrometry and Fourier transform infrared spectroscopy. Yeast 1998, 14 (10): 885-93
• Fernandes SM, Rangel AO, Files JL. Merging zones for standard addition technique determination of to cooper in beer by flow injection atomic absorption spectrophotometry. J AOAC Int 1998, 81 (3): 645-7
• Towers MR, Sanchís V, Branches AJ. Ocurrence of fumonisins in Spain beers analyzed by an enzyme-linked immunosorbent assay method. Int J Food Microbiol 1998, 39 (1-2): 139-43
• Linssen JP, Rijnen L, Legger-Huiysman To, Roozen JP. Combined GC and sniffing port analysis of volatile compounds in rubber rings mounted on to beer bottles. Food Addit Contam 1998, 15 (1): 79-83
• Saungweme T, Khumalo H, Mvundura and, Moyo VM, Gordeux VR, Rouault TA ET to. Iron and traditional alcohol content of beers in rural Zimbabwe
• Rasmussen LB, Larsen EH, Ovesen L. Iodine content in drinking to water and to other beverages in Denmark. Eur J Clin Nutr 2000, 54 (1): 57-60
• Hirt M, Cechova and, Fialka J, Hottmar P, Loyka S, Mraz J ET to. Overview of the canges in alcohol content of beers produced in the Czech Republic. Soud Lek 1999, 44 (4): 47-54
• Zollner P, Berner D, Jodlbauer J, Lindner W. Determination of zearalenone and its metabolites alpha- and beta zearalenol in beer samples by high-performance liquid chromatography-tandem mass spectrometry. J Chromatogr B Biomed Sci App 2000, 738 (2): 233-41
• Gorinstein S, Zemser M, Vargas Dawn F, Ochoa JL, Walls Lopez Or, Scheler CH ET to. Amino Proteins and acids in beers, to their contents and relationships wiht to other analytical data. Food Chem 1999, 67 (1): 71-78
• Candle MM, Taking RB, Reiboldt W, Pierri A. Detection of aluminum residue in fresh and stored canned to beer. Food Chem 1998, 63 (2): 235-239
• CASE GA, Distefano S, Logan BK. Tabulation of alcohol content of to beer and malt beverages. Anal J Toxicol 2000 24 (3): 202-10
• Hill PG, Smith RM. Determination of sulfur compounds in beer using headspace solid-phase microextraction and gas chromatographic analysis wiht pulsed flame photometric detection. J Chromatrog To 2000, 872 (1-2): 203-13
• Perez Ruiz T, Martinez-Lozano C, Takings V, Martin J. Flow injection determination of lactate based on to photochemical reaction using photometric and chemiluminescence detection. Analyst 1999, 124 (10): 1517-21
• Satokari R, Mattila-Sandholm T, Suihko ML Identification of pediococci by ribotyping. J Appl Microbiol 2000, 88 (2): 260-5
• Horsted MW, Dey IS, Holmberg S, Klelland-Brandt MC. To Nobel it would cover with mats from Saccharomyces carlsbergensis, to for possible function the yeast TIP1 gene. Yeast 1998, 14 (9): 793-803.
• Zuskin and, Mustajbegovic J, Sitar-Srebocan V.Pharmacologic study of the effects of the components of to beer test-tube. Lijeclicki Vjesnik 1997, 119 (3-4): 103-5

As of this moment (and with a total of 233 references) two parallel lines based on the indicated objectives are followed previously:

• Narrative revision, of the Literature published on the consumption of beer and its possible effects on the human health
• Put-analysis regarding the consumption of beer and its effects on the human health