DeCS 2020 - Instructions for updating strategies used in searching thematic areas of the VHL

In view of the annual update carried out in the MeSH vocabulary which is then incorporated into DeCS, as well as changes in other DeCS categories, the need for the revision and update of the search strategies of the thematic areas of the VHL have become crucial. This revision applies both to the strategies that use descriptors as well as to those using hierarchic codes.

To achieve the update of the strategies, the addresses for the two versions of DeCS Search are available, where queries using the alphabetical, hierarchic and kwic (keyword in context) indices can be made:

  • version 2019 from which the strategies were based: DeCS 2019 Search 

  • version 2020 from which the strategies must now be based: DeCS 2020 Search
  • Besides the information available under DeCS News regarding the changes occurred in 2020 (DeCS 2020 edition), the link under DeCS previous editions, for the 2006 edition, contains more detailed information with respect to the important revision of the Public Health category, that brought many modifications.

    In order to update search strategies containing hierarchic codes (or tree numbers), see the MeSH and DeCS tree number changes taken place between the years 2019 y 2020.

    Methodology for updating search strategies

  • In the DeCS 2020 Search, look for the descriptor in the existing strategy using the Exact Descriptor field, or search the hierarchical code in the existing strategy using the tree index to see if it still exists;

  • If it exists, fine;

  • If the descriptor is not found, check in the list of changed descriptors and in the list of deleted descriptors on the DeCS 2020 edition news page and update its strategy with the descriptor that replaced (or absorbed) it;

  • If the hierarchical code is not found, search for it in the tree index of the DeCS 2019 Search and find out the descriptor to which it used to belong; then search for this descriptor using the Exact Descriptor option at DeCS 2020 Search to find out if it still exists and, if so, what its valid hierarchical code is;

  • Example of a descriptor that suffered a hierarchical code (also called tree number) change:

    Appetite Regulation: available both in 2016 and in 2017 in DeCS's G category - Phenomena and Processes. In 2016 it was positioned under the descriptors Appetite and Nutrition Processes, and had the hierarchical codes G07.203.650.390.070.290, G07.203.650.593.080, G07.700.620.080, and G10.261.390.070.290In 2017 it was repositioned in the second and third hierarchical branches; instead of staying under Nutrition Processes, it is now under the descriptor Nutritional Physiological Phenomena, having the hierarchical code G07.203.650. Note the changes to these branches in the tree views for these two years:

                DeCS 2016

            PHENOMENA AND PROCESSES [G]
              Physiological Phenomena [G07]
                Diet, Food, and Nutrition [G07.203]
                  Nutritional Physiological Phenomena [G07.203.650]
                    Nutrition Processes [G07.203.650.593]
                        Appetite Regulation [G07.203.650.593.080]

            PHENOMENA AND PROCESSES  [G]
              Physiological Phenomena [G07]
                Physiological Processes [G07.700]
                  Nutrition Processes [G07.700.620]
                      Appetite Regulation[G07.700.620.080]

                DeCS 2017

            PHENOMENA AND PROCESSES [G]
              Physiological Phenomena [G07]
                Diet, Food and Nutrition [G07.203]
                   Nutritional Physiological Phenomena [G07.203.650]
                      Appetite Regulation [G07.203.650.170]

    This update should happen in all strategies where the hierarchical codes G07.203.650.593.080 y G07.700.620.080 is used in place of the descriptor Appetite Regulation.

  • See below an example of the search strategy for the descriptor Pesticides, valid until 2004 and its updated strategy for 2006, due to the last big revision to the Public Health category:

    Before updating:

    (ex SP4.405.350.364$ or ex SP8.473.654.412.052.080.115.020.020$ or ex D05.723$ or ex D27.720.723$) or (ti Pesticide$ or ti Plaguicida$ or ti Praguicida$) [Subject descriptor]

    Updating that was made:

          SP4.405.350.364

  • This hierarchic code which in 2004 corresponded to the Pesticides descriptor in SP4 (Environmental Health) was modified. The new 2006 hierarchic code for the descriptor in the SP4 (Environmental Health) category is: SP4.001.022.238.

    Explode, truncation

    The "ex" (from explode) that precedes the hierarchic code and the "$" sign (truncation), indicate that the Pesticidesdescriptor and all its more specific descriptors will be included in the recovery of literature.

    SP8.473.654.412.052.080.115.020.020

    This hierarchic code, that continues to exist, also belongs to the Pesticides descriptor since, being DeCS polyhierarchical, a descriptor can be located in more than one of its categories/subcategories. It is not necessary to again include in the strategy this descriptor or the other hierarchic branch where the descriptor is found, because it is already also duly contemplated in SP4.001.022.238.

    Unnecessary truncation

    Another detail for the elaboration of the strategies is that when a hierarchic code of a descriptor is used under which there is no other more specific descriptor, it is unnecessary to follow it with the "$" sign.

    D05.723

    This hierarchic code does no longer appear in version 2004 of DeCS, since the D05 subcategory of MeSH was eliminated in 2004. Its content was transferred to the D27.888 subcategory. In 2005 the D05 subcategory was recreated by MeSH but with other content: Macromolecular Substances.

    Title words

    The words of the title continue in the search strategy expression without alterations.

    Pesticides [D27.720.723] and Pesticides [D27.888.723]

    These hierarchic branches are almost identical, except for the descriptor Pesticide Residues, present in the D27.888.723 branch and absent in the D27.720.723 branch.

    One should remember that the same descriptor can be inserted in different hierarchies in the DeCS tree, with variations in the specific descriptors. If it is necessary to consider different specific descriptors, the different hierarchic branches can be included in the strategy.

    Final recommendation

    Thus, contemplating all the existing specific descriptors in the various hierarchic branches where the descriptor Pesticides is inserted, the new search strategy must be as follows:

    (ex SP4.001.022.238$ or ex D27.888.723$) [Subject descriptor] or (ti Pesticide$ or ti Plaguicida$ or ti Praguicida$) [Title words]

    The hierarchical branches cited in the example above, in the two versions of DeCS:

    DeCS 2004

    Pesticides  [D27.720.723]
                Chemosterilants [D27.720.723.141]
                Fungicides, Industrial [D27.720.723.288]
                Herbicides [D27.720.723.366]
                   Defoliants, Chemical [D27.720.723.366.181]
                   Herbicides, Carbamate [D27.720.723.366.448]
                   Herbicides, Triazine [D27.720.723.366.477]
                   Herbicides, Urea [D27.720.723.366.506]
                Insect Repellents [D27.720.723.441]
                Insecticides [D27.720.723.491]
                   Insecticides, Botanical [D27.720.723.491.324]
                   Inseticides, Carbamate [D27.720.723.491.408]
                   Insecticides, Organochlorine [D27.720.723.491.491]
                   Insecticides, Organophosphate [D27.720.723.491.574]
                   Insecticides, Organotiophosphate [D27.720.723.491.657]
                Molluscacides [D27.720.723.596]
                Pesticide Synergists [D27.720.723.748]
                Rodenticides [D27.720.723.853]

    Pesticides [D27.888.723]
                Chemosterilants [D27.888.723.141]
                Fungicides, Industrial [D27.888.723.288]
                Herbicides [D27.888.723.366]
                   Defoliants, Chemical [D27.888.723.366.181]
                   Herbicides, Carbamate [D27.888.723.366.448]
                   Herbicides, Triazine [D27.888.723.366.477]
                   Herbicides, Urea [D27.888.723.366.506]
                Insect Repellents [D27.888.723.441]
                Insecticides [D27.888.723.491]
                   Insecticides, Botanical [D27.720.723.491.324]
                   Insecticides, Carbamate [D27.720.723.491.408]
                   Insecticides, Organochlorine [D27.720.723.491.491]
                   Insecticides, Organophosphate [D27.720.723.491.574]
                   Insecticides, Organotiophosphate [D27.720.723.491.657]
                Molluscacides [D27.888.723.596]
                Pesticide Residues [D27.888.723.697]
                Pesticide Synergists [D27.888.723.748]
                Rodenticides [D27.888.723.853]

    Pesticides [SP4.405.350.364]
                   Algicides [SP4.405.350.364.204]
                   Bactericides [SP4.405.350.364.205]
                      Bacteriophages [SP4.405.350.364.205.410]
                   Fungicides, Industrial [SP4.405.350.364.206]
                   Herbicidae [SP4.405.350.364.207]
                   Pesticide Utilization [SP4.405.350.364.309]

    Pesticides [SP8.473.654.412.052.080.115.020.020]

    DeCS 2006

    Pesticides [D27.720.723]
                Chemosterilants [D27.720.723.141]
                Fungicides, Industrial [D27.720.723.288]
                Herbicides [D27.720.723.366]
                   Defoliants, Chemical [D27.720.723.366.181]
                Insect Repellents [D27.720.723.441]
                Insecticides [D27.720.723.491]
                Molluscacides [D27.720.723.596]
                Pesticide Synergists [D27.720.723.748]
                Rodenticides [D27.720.723.853]

    Pesticides [D27.888.723]
                Chemosterilants [D27.888.723.141]
                Fungicides, Industril [D27.888.723.288]
                Herbicides [D27.888.723.366]
                   Defoliants, Chemical [D27.888.723.366.181]
                Insect Repellents [D27.888.723.441]
                Insecticides [D27.888.723.491]
                Molluscacides [D27.888.723.596]
                Pesticide Residues [D27.888.723.697]
                Pesticide Synergists [D27.888.723.748]
                Rodenticides [D27.888.723.853]

    Pesticides [SP4.001.022.238]
                Creosote [SP4.001.022.238.349]
                Algicides [SP4.001.022.238.354]
                Bactericides [SP4.001.022.238.359]
                Fungicides, Industrial [SP4.001.022.238.364]
                Herbicides [SP4.001.022.238.369]
                Insect Repellents [SP4.001.022.238.374]
                Rodenticides [SP4.001.022.238.379]
                Larvicides [SP4.001.022.238.384]
                Insecticides [SP4.001.022.238.389]
                   Carbaryl [SP4.001.022.238.389.215]
                   Carbamates [SP4.001.022.238.389.220]
                   Carbofuran [SP4.001.022.238.389.225]
                   Insecticides, Organochlorine [SP4.001.022.238.389.230]
                      Aldrin [SP4.001.022.238.389.230.036]
                      Chlordan [SP4.001.022.238.389.230.041]
                      Dichlorodiphenyldichloroethane [SP4.001.022.238.389.230.046]
                      DDT [SP4.001.022.238.389.230.051]
                      Dieldrin [SP4.001.022.238.389.230.056]
                      Endrin [SP4.001.022.238.389.230.061]
                      Heptachlor [SP4.001.022.238.389.230.066]
                      Toxaphene [SP4.001.022.238.389.230.071]
                   Insecticides, Organophosphate [SP4.001.022.238.389.235]
                      Diazinon [SP4.001.022.238.389.235.076]
                      Malathion [SP4.001.022.238.389.235.081]
                      Parathion [SP4.001.022.238.389.235.086]
                         Methyl Parathion [SP4.001.022.238.389.235.086.022]

    Pesticides [SP8.473.654.412.052.080.115.020.020]

    Last Updated: 06/04/2020