Ucwaningo lokucwaninga luhlolisiso lwe-epidemiological ucwaningo olungafaki ukungenelela noma ukuhlolwa. Izihloko zifundwa ngaphansi kwezimo zokuphila zemvelo.
Ososayensi basebenzisa izifundo zokuhlola ukuzingela ubuhlobo obukhona phakathi kokuchayeka nemiphumela. Zisetshenziselwa izindawo eziningana zezempilo, futhi eziningi zezifundo ozizwayo ku-TV noma ukufunda ngazo kumawebhusayithi, omagazini, namaphephandaba yizifundo zokuhlola.
'Umphumela' ngokuvamile uyisifo noma inkinga yezempilo ngenye indlela.
Ososayensi basebenzisa ulwazi oluvela ezintweni ezifana nokuhlola kanye namarekhodi wezokwelapha ukuze ubone izifundo ezithile zinento ethile noma izinto ezifanayo. Lezi zinto zibizwa ngokuthi 'ukuchayeka.' Uma inani eliphelele locwaningo lubonisa ukuthi ukuvezwa kwandisa ingozi yomphumela, khona-ke ukuchazwa kwaziwa njengengozi engozini. Isibonelo sokuchayeka kuyisimo esiyingozi kungadla inyama enkulu eyenziwe inyama , okuyinto engozini yokuthuthukisa izinhlobo ezithile zomdlavuza. Ngezinye izikhathi ukugcoba kungaba yisivikelo, njengokudla ukudla okunezithelo nemifino, okubonakala kunciphisa ingozi yesifo senhliziyo.
Izinhlobo
Ucwaningo oluningi lokubheka luwela kwesinye sezigaba ezintathu, izifundo / izicwaningo zokulawula, izifundo zocwaningo / izifundo ezihamba phambili.
Ucwaningo / ucwaningo luqala ngeqembu lezifundo ezinomphumela wokufundwa (amacala) kanye namanye amaqembu alabo abangenawo (ukulawula).
Ososayensi babuye babuye emuva ngesikhathi ukuze babone ukuthi amacala ayenoma yini ejwayelekile ukuthi izilawuli azikho noma ngokufanayo. Ucwaningo / ucwaningo lubizwa ngokuthi izifundo zokubuyela emuva ngoba ziqala ngomphumela bese ubukeka emuva esikhathini.
Ucwaningo lwezinkampani lithatha inqwaba yezihloko futhi zibahlukanise ngokuchayeka, bese zilandela isikhathi esithile (kaningi iminyaka namashumi eminyaka) ukubona ukuthi ubani othuthukisa umphumela abawufundelayo.
Kanti, ososayensi bafuna ukubona ukuthi amalunga kunoma yiliphi lamaqembu anezici ezifanayo.
Ucwaningo lwamaqembu luqala ngaphambi kokuba noma ubani abe nomphumela futhi abheke phambili ngesikhathi, ngakho abizwa ngokuthi abazoba khona. Ososayensi bangadingeka balinde iminyaka ngemiphumela ngaphandle kokuthi basebenzise isifundo esikhulu esiqhubekayo, njenge-National Health and Nutrition Examinations Survey (NHANES). Izinkulungwane zabantu zibamba iqhaza minyaka yonke ngokuphendula imibuzo nokuhlolwa okungokwenyama. Ososayensi baphenya ngolwazi oluqoqwe kusuka ku-NHANES ukuzohlola zonke izinhlobo zokuxhumana phakathi kokudla, izithako zokudla kanye nempilo. Isibonelo, ulwazi lwe-NHANES lusetshenziselwa ukucacisa ukuthi ukulandelana (i-vitamin B-complex) kungabangela ukukhubazeka kokuzalwa.
Izifundo ezithinta izigaba azibheki phambili noma emuva; babheka kuphela ukuthi kwenzekani ngesikhathi esisodwa. Ososayensi banganquma ukuthi bangaki abantu abanomphumela wesithakazelo futhi bazama ukubheka ukuchayeka, kodwa ngaphandle kwesikhathi eside, kunzima ukwazi ngokuqinisekile.
Amandla nobuthakathaka
Izifundo zokuqapha ziningi kakhulu, kaningi ngezinkulungwane zabahlanganyeli, okunika amandla emiphumeleni, kepha ngokuvamile abakwazi ukucacisa noma yikuphi imbangela. Njengoba izifundo zihlala ngendlela evamile, ngokuvamile kuvame ukutholakala okuningi okungahle kuphazamise imiphumela.
Isibonelo ekufundeni okuningi kokudla, abantu abadla inyama enkulu ebomvu nabo bathambekele ekubhemeni, badle ama-fibre amancane, futhi basebenzise kancane kunesilinganiso. Izikhonzi ezidla inyama encane yobomvu zibuye zisebenzise okuningi, zidle izithelo nemifino ngaphezulu kunezilinganiso, futhi zivame ukubhema.
Ososayensi basebenzisa izindlela ezihlukahlukene zokubala ukususa izici ezingase ziphazamise, kodwa ngezinye izikhathi imiphumela isaluthola kancane. Ngezinye izikhathi imiphumela yezifundo zokuhlola ziholela ekuhlolweni okulawulwa ngokungahleliwe (RCT), okuyizinhlelo zokungenelela, noma ukuhlola, nokucabangela ukunikeza ubufakazi obuhle kakhulu bokucwaninga.
Kungenxa yokuthi izihloko zihlelwe ngezigaba zokwelapha nokulawula, okunciphisa imiphumela yezinto eziphazamisayo.
Imithombo:
Amasevisi Okulawula Nokuvimbela Izifo. "Mayelana neNational Health and Nutrition Examination Survey." http://www.cdc.gov/nchs/nhanes/about_nhanes.htm.
UJepsen P, uJohnsen P, uGillman MW, uSørensen HT. "Ukuchazwa kwezifundo zokuhlola." Inhliziyo. 2004 Agasti; 90 (8): 956-960. http://heart.bmj.com/content/90/8/956