anchor.diff:  
   === Eligibility criteria
   
  -Studies and associations are eligible for inclusion in the NHGRI GWAS catalog if they meet the following criteria:
  +Studies and associations are eligible for inclusion in the NHGRI-EBI GWAS Catalog if they meet the following criteria:
   
   * Include a primary GWAS analysis, defined as array-based genotyping and analysis of 100,000+ pre-QC SNPs selected to tag variation across the genome and without regard to gene content.
   * GWAS data from published studies which are incorporated into new GWAS analyses are eligible, provided they meet the other criteria.
  
positive.code: 
  For each identified SNP, we extract:
  
  * REPORTED GENE: Gene(s) reported by the author; "Intergenic" is used to denote a reported intergenic location (or lack of gene if it appeared that gene information was sought); “NR” is used to denote that no gene location information was reported.
  * STRONGEST SNP-RISK ALLELE: SNP(s) most strongly associated with trait + risk/effect allele (? for unknown risk allele). May also refer to a haplotype.
  * SNPS: Strongest SNP; If a haplotype is reported above, this field may include more than one rs number (multiple SNPs comprising the haplotype). Multiple SNPs may also be included if proxy SNPs are reported.
  * RISK ALLELE FREQUENCY: Reported risk/effect allele frequency associated with strongest SNP in controls (if not available among all controls, among the control group with the largest sample size). If the associated locus is a haplotype the haplotype frequency will be extracted.
  * P-VALUE: Reported p-value for strongest SNP risk allele. Note that p-values are rounded to 1 significant digit (for example, a published p- value of 4.8 x 10-7 is rounded to 5 x 10-7).
  * PVALUE_MLOG: -log(p-value)
  * P-VALUE (TEXT): Information describing context of p-value (e.g. females, smokers).
  * OR or BETA: Reported odds ratio or beta-coefficient associated with strongest SNP risk allele. Note that if an OR <1 is reported this is inverted, along with the reported allele, so that all ORs included in the Catalog are >1. Appropriate unit and increase/decrease are included for beta coefficients.
  * 95% CI (TEXT): Reported 95% confidence interval associated with strongest SNP risk allele, along with unit in the case of beta-coefficients. If 95% CIs are not published, we estimate these using the standard error, where available.
  
negative.code: Papers that qualify for inclusion in the Catalog are identified through weekly PubMed searches.
  They then undergo two levels of curation.
  First all data, including association information for SNPs, traits and general information about the study, are extracted by one curator.
  A second curator then performs an additional round of curation to double-check the accuracy and consistency of all the information. Finally, an automated pipeline performs validation of the extracted data, see the <<mapping, Quality control and SNP mapping section>> below for more details. This information is then used for queries and in the production of the diagram.
  
  
  == Full Description of Methods
  