WordNet

look over, usually with the intention to rob; "They men cased the housed"
the quantity contained in a case (同)caseful
a specific state of mind that is temporary; "a case of the jitters"
(printing) the receptacle in which a compositor has his type, which is divided into compartments for the different letters, spaces, or numbers; "for English, a compositor will ordinarily have two such cases, the upper case containing the capitals and the lower case containing the small letters" (同)compositor''s case, typesetter''s case
a glass container used to store and display items in a shop or museum or home (同)display case, showcase, vitrine
bed linen consisting of a cover for a pillow; "the burglar carried his loot in a pillowcase" (同)pillowcase, slip, pillow slip
a portable container for carrying several objects; "the musicians left their instrument cases backstage"
nouns or pronouns or adjectives (often marked by inflection) related in some way to other words in a sentence (同)grammatical case
an occurrence of something; "it was a case of bad judgment"; "another instance occurred yesterday"; "but there is always the famous example of the Smiths" (同)instance, example
a person requiring professional services; "a typical case was the suburban housewife described by a marriage counselor"
a problem requiring investigation; "Perry Mason solved the case of the missing heir"
a statement of facts and reasons used to support an argument; "he stated his case clearly"
the actual state of things; "that was not the case"
verify by using a duplicate register for comparison; "control an account"
a relation of constraint of one entity (thing or person or group) by another; "measures for the control of disease"; "they instituted controls over drinking on campus"
a mechanism that controls the operation of a machine; "the speed controller on his turntable was not working properly"; "I turned the controls over to her" (同)controller
(physiology) regulation or maintenance of a function or action or reflex etc; "the timing and control of his movements were unimpaired"; "he had lost control of his sphincters"
the activity of managing or exerting control over something; "the control of the mob by the police was admirable"
a spiritual agency that is assumed to assist the medium during a seance
power to direct or determine; "under control"
the economic policy of controlling or limiting or curbing prices or wages etc.; "they wanted to repeal all the legislation that imposed economic controls"
exercise authoritative control or power over; "control the budget"; "Command the military forces" (同)command
lessen the intensity of; temper; hold in restraint; hold or keep within limits; "moderate your alcohol intake"; "hold your tongue"; "hold your temper"; "control your anger" (同)hold in, hold, contain, check, curb, moderate
check or regulate (a scientific experiment) by conducting a parallel experiment or comparing with another standard; "Are you controlling for the temperature?" (同)verify
be a student; follow a course of study; be enrolled at an institute of learning
a room used for reading and writing and studying; "he knocked lightly on the closed door of the study"
applying the mind to learning and understanding a subject (especially by reading); "mastering a second language requires a lot of work"; "no schools offer graduate study in interior design" (同)work
a composition intended to develop one aspect of the performers technique; "a study in spiccato bowing"
a state of deep mental absorption; "she is in a deep study"
someone who memorizes quickly and easily (as the lines for a part in a play); "he is a quick study"
give careful consideration to; "consider the possibility of moving" (同)consider
learn by reading books; "He is studying geology in his room"; "I have an exam next week; I must hit the books now" (同)hit the books
think intently and at length, as for spiritual purposes; "He is meditating in his study" (同)meditate, contemplate
provide with or construct with studs; "stud the wall"
ornament consisting of a circular rounded protuberance (as on a vault or shield or belt) (同)rivet
poker in which each player receives hole cards and the remainder are dealt face up; bets are placed after each card is dealt (同)stud poker
adult male horse kept for breeding (同)studhorse
a man who is virile and sexually active (同)he-man, macho-man
the enclosing frame around a door or window opening; "the casings had rotted away and had to be replaced" (同)case
the outermost covering of a pneumatic tire

PrepTutorEJDIC

〈C〉(…の)『実例』,事例《+『of』+『名』》 / 《the case》『実情』,真相 / 〈C〉〈U〉『場合』,情況,事情,立場 / 〈C〉(…の)(決定すべき)問題,重大事《+『of』+『名』》 / 〈C〉『訴訟』[『事件』],裁判 / 〈C〉(正当な)論拠,弁護;(被告または原告の)主張,申し立て / 〈C〉病状,容態;(症状から見た)患者 / 〈C〉〈U〉格(名詞・代名詞の語形変化)
(運搬・保管用のいろいろな)『箱』,ケース / (各種の)『容器』,筒,さや,袋,おおい / (標本・陳列用の)ガラス箱,戸だな / (戸・窓などの)わく / 活字箱 / …'を'箱(袋,さやなど)に入れる《+『名』+『up,』+『名』+『up』》
〈U〉(…に対する)『統制』,抑制,制御《+『over』(『of』+『名』) / 〈C〉《複数形で》(…を)統整する手段,統御法《+『on』(『over』)+『名』》 / 〈U〉(…を)『抑制する力』,(…の)統整力,支配力《+『over』(『of』)+『名』》 / 《複数形で》《単数扱い》(機械の)操縦装置 / 〈C〉(実験結果の)照査基準 / …'を'『支配する』,統御する,管理する,監督する / 〈感情など〉'を'『抑制する』,抑える / …'を'照らし合わせて調べる,照査する
〈U〉(一般に)『勉強』,学習すること / 〈C〉(…の)勉強,研究《+of+名》 / 〈C〉〈U〉(…の)『綿密な調査』,検討《+of+名》 / 〈C〉研究対象(問題,事項);学科 / 〈C〉『書斎』,勉強部屋 / 〈C〉(美術・文学などの)習作,試作,スケッチ,(音楽の)練習曲,エチュード / …‘を'『勉強する』,学ぶ,研究する / …‘を'『よく注意して見る』,しげしげと見る / …‘を'『調査する』,検討する / …‘を'考慮する,配慮する / 〈せりふなど〉‘を'覚えようとする / 『勉強する』,学ぶ,研究する
《おもに米》種馬 / 《集合的に》(一群の)繁殖用動物(種馬,種牛など)
(インテリアなどに用いる)飾りびょう / カフスボタン,カラーボタン / (建物の)間柱 / (…を)…‘に'ちりばめる《+名+with+名》 / …‘に'点在(散在)している / …‘に'間柱をつける
箱,包装,おおい / (電線・タイヤなどの)被覆,(ソーセージの)皮 / (ドア・窓などの)わく;額縁

Wikipedia preview

出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2014/10/19 19:08:10」(JST)

wiki en

Case-Control Study vs. Cohort on a Timeline

A case-control study is a type of study design used widely, originally developed in epidemiology, although its use has also been advocated for the social sciences.^[1]^[2] It is a type of observational study in which two existing groups differing in outcome are identified and compared on the basis of some supposed causal attribute. Case-control studies are often used to identify factors that may contribute to a medical condition by comparing subjects who have that condition/disease (the "cases") with patients who do not have the condition/disease but are otherwise similar (the "controls").^[3] They require fewer resources but provide less evidence for causal inference than a randomized controlled trial.

Definition

The case-control is a type of epidemiological observational study. An observational study is a study in which subjects are not randomized to the exposed or unexposed groups, rather the subjects are observed in order to determine both their exposure and their outcome status and the exposure status is thus not determined by the researcher. Porta's Dictionary of Epidemiology^[4] defines the case-control study as: an observational epidemiological study of persons with the disease (or another outcome variable) of interest and a suitable control group of persons without the disease (comparison group, reference group). The potential relationship of a suspected risk factor or an attribute to the disease is examined by comparing the diseased and nondiseased subjects with regard to how frequently the factor or attribute is present (or, if quantitative, the levels of the attribute) in each of the groups (diseased and nondiseased)."^[4]

For example, in a study trying to show that people who smoke (the attribute) are more likely to be diagnosed with lung cancer (the outcome), the cases would be persons with lung cancer, the controls would be persons without lung cancer (not necessarily healthy), and some of each group would be smokers. If a larger proportion of the cases smoke than the controls, that suggests, but does not conclusively show, that the hypothesis is valid.

The case-control study is frequently contrasted with cohort studies, wherein exposed and unexposed subjects are observed until they develop an outcome of interest.^[4]^[5]

Control group selection

Controls need not be in good health; inclusion of sick people is sometimes appropriate, as the control group should represent those at risk of becoming a case.^[6] Controls should come from the same population as the cases, and their selection should be independent of the exposures of interest.^[7]

Controls can carry the same disease as the experimental group, but of another grade/severity, therefore being different from the outcome of interest. However, because the difference between the cases and the controls will be smaller, this results in a lower power to detect an exposure effect.

As with any epidemiological study, greater numbers in the study will increase the power of the study. Numbers of cases and controls do not have to be equal. In many situations, it is much easier to recruit controls than to find cases. Increasing the number of controls above the number of cases, up to a ratio of about 4 to 1, may be a cost-effective way to improve the study.^[8]

Strengths and weaknesses

Case-control studies are a relatively inexpensive and frequently used type of epidemiological study that can be carried out by small teams or individual researchers in single facilities in a way that more structured experimental studies often cannot be. They have pointed the way to a number of important discoveries and advances. The case-control study design is often used in the study of rare diseases or as a preliminary study where little is known about the association between the risk factor and disease of interest.^[9]

Compared to prospective cohort studies they tend to be less costly and shorter in duration. In several situations they have greater statistical power than cohort studies, which must often wait for a 'sufficient' number of disease events to accrue.

Case-control studies are observational in nature and thus do not provide the same level of evidence as randomized controlled trials. The results may be confounded by other factors, to the extent of giving the opposite answer to better studies. A meta-analysis of what were considered 30 high-quality studies concluded that use of a product halved a risk, when in fact the risk was, if anything, increased.^[10]^[11] It may also be more difficult to establish the timeline of exposure to disease outcome in the setting of a case-control study than within a prospective cohort study design where the exposure is ascertained prior to following the subjects over time in order to ascertain their outcome status. The most important drawback in case-control studies relates to the difficulty of obtaining reliable information about an individual’s exposure status over time. Case-control studies are therefore placed low in the hierarchy of evidence.

Examples

One of the most significant triumphs of the case-control study was the demonstration of the link between tobacco smoking and lung cancer, by Richard Doll and Bradford Hill. They showed a statistically significant association in a large case-control study.^[12] Opponents argued for many years that this type of study cannot prove causation, but the eventual results of cohort studies confirmed the causal link which the case-control studies suggested,^[13]^[14] and it is now accepted that tobacco smoking is the cause of about 87% of all lung cancer mortality in the US.

Analysis

Case-control studies were initially analyzed by testing whether or not there were significant differences between the proportion of exposed subjects among cases and controls.^[15] Subsequently Cornfield^[16] pointed out that, when the disease outcome of interest is rare, the odds ratio of exposure can be used to estimate the relative risk (see rare disease assumption). It was later shown by Miettinen in 1976 that this assumption is not necessary and that the odds ratio of exposure can be used to directly estimate the incidence rate ratio of exposure without the need for the rare disease assumption.^[15]^[17]^[18]

References

^ Forgues, B. 2012. Sampling on the Dependent Variable Is Not Always That Bad: Quantitative Case-Control Designs for Strategic Organization Research. Strategic Organization, 10(3): 269-275.
^ Lacy, M. G. 1997. Efficiently Studying Rare Events: Case-Control Methods for Sociologists. Sociological Perspectives, 40(1): 129-154.
^ "8. Case-control and cross sectional studies". Retrieved March 5, 2012.
^ ^a ^b ^c Porta M (editor). A dictionary of epidemiology. 5th. edition. New York: Oxford University Press, 2008. Edited by Miquel Porta [1]
^ Rothman K. Epidemiology. An Introduction. Oxford University Press, Oxford, England, 2002. [2]
^ Compared to what? Finding controls for case-control studies, David A Grimes, Kenneth F Schulz, Lancet 2005; 365: 1429–33
^ Case-control studies: research in reverse; Kenneth F Schulz, David A Grimes. Lancet 2002: 359: 431–34
^ Grimes D.A., Schulz K.F. Compared to what? Finding controls for case-control studies. Lancet 2005; 365: 1429–33
^ Levin, K. A. (2005). "Study design I". Evidence-Based Dentistry 6 (3): 78–79. doi:10.1038/sj.ebd.6400355. PMID 16184164. edit
^ Lawlor, D. A., G. Davey Smith, and S. Ebrahim. 2004. Commentary: The hormone replacement-coronary heart disease conundrum: is this the death of observational epidemiology? Int. J. Epidemiol. 33: 464-467.
^ Ioannidis, J. P. A. 2005. Contradicted and initially stronger effects in highly cited clinical research. JAMA 294: 218-228.
^ Doll & Hill (1950). Smoking and carcinoma of the lung; preliminary report. BMJ, 2, 739. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2038856/
^ Doll & Hill (1956). Lung cancer and other causes of death in relation to smoking; a second report on the mortality of British doctors. BMJ, 2, 1071.
^ Doll et al. (2004). Mortality in relation to smoking: 50 years’ observations on male British doctors. BMJ, 328, 1507.
^ ^a ^b Rodrigues L, Kirkwood BR. Case-control designs in the study of common diseases: updates on the demise of the rare disease assumption and the choice of sampling scheme for controls. International J of Epidemiology 1990; 19(1):205-13. [3]
^ Greenhouse SW. Jerome Cornfield’s contributions to epidemiology. Biometrics 1982; 38:33-45. [4]
^ Miettinen OS. Estimability and estimation in case-referent studies. Am J Epidemiol 1976; 103:226-236. [5]
^ Rothman KJ, Greenland S, Lash TL. Modern Epidemiology. 3rd edition. Wolters Kluwer, Lippincott Williams & Wilkins. 2008. [6]

External links

Wellcome Trust Case Control Consortium

UpToDate Contents

全文を閲覧するには購読必要です。 To read the full text you will need to subscribe.

1. 生物統計学および疫学に関する一般用語集 glossary of common biostatistical and epidemiological terms
2. 早期再分極 early repolarization
3. アスピリンの無効および耐性 nonresponse and resistance to aspirin
4. HIV感染患者における心血管疾患の病因およびバイオマーカー pathogenesis and biomarkers of cardiovascular disease in hiv infected patients
5. SIDSを含む乳児の予期せぬ死亡：初期マネージメント sudden unexpected infant death including sids initial management

English Journal

Factors affecting bone mineral density in postmenopausal women.

Heidari B1, Hosseini R, Javadian Y, Bijani A, Sateri MH, Nouroddini HG.
Archives of osteoporosis.Arch Osteoporos.2015 Dec;10(1):217. doi: 10.1007/s11657-015-0217-4. Epub 2015 May 14.
This study aimed to determine the relationship between bone mineral density (BMD) and demographic, biochemical, and clinical features according to BMD measurement sites. The results indicated that BMD correlates negatively with menopause duration, parity, and history of fractures but positively corr
PMID 25972061

Breast cancer risk and genetic ancestry: a case-control study in Uruguay.

Bonilla C1, Bertoni B, Hidalgo PC, Artagaveytia N, Ackermann E, Barreto I, Cancela P, Cappetta M, Egaña A, Figueiro G, Heinzen S, Hooker S, Román E, Sans M, Kittles RA.
BMC women's health.BMC Womens Health.2015 Dec;15:171. doi: 10.1186/s12905-015-0171-8. Epub 2015 Feb 18.
BACKGROUND: Uruguay exhibits one of the highest rates of breast cancer in Latin America, similar to those of developed nations, the reasons for which are not completely understood. In this study we investigated the effect that ancestral background has on breast cancer susceptibility among Uruguayan
PMID 25783644

Case-control study of ADARB1 and ADARB2 gene variants in migraine.

Gasparini CF1, Sutherland HG, Maher B, Rodriguez-Acevedo AJ, Khlifi E, Haupt LM, Griffiths LR.
The journal of headache and pain.J Headache Pain.2015 Dec;16(1):511. doi: 10.1186/s10194-015-0511-y. Epub 2015 Apr 3.
BACKGROUND: Migraine causes crippling attacks of severe head pain along with associated nausea, vomiting, photophobia and/or phonophobia. The aim of this study was to investigate single nucleotide polymorphisms (SNPs) in the adenosine deaminase, RNA-specific, B1 (ADARB1) and adenosine deaminase, RNA
PMID 25916332

Japanese Journal

Increased risk of acute pancreatitis in patients with type 2 diabetes: an observational study using a Japanese hospital database.

Urushihara Hisashi,Taketsuna Masanori,Liu Ying,Oda Eisei,Nakamura Masaki,Nishiuma Shinichi,Maeda Rei
PloS one 7(12), 2012-12-27
… the odds ratios associated with diabetes mellitus and other comorbid risk factors were estimated with separate case-control analyses. … The adjusted odds ratio of acute pancreatitis in patients with diabetes mellitus was 1.86 (P<0.001) compared with non-diabetic patients in case-control analysis from 1,372 cases and 5,469 matched controls, which is consistent with the ones reported in previous studies. …
NAID 120005173553

学位論文解説高齢口腔扁平上皮癌患者における上部消化管癌の重複に関する検討

伊川裕明
歯科学報 112(6), 709-713, 2012-12-00
NAID 40019560985

膵β細胞機能に着目したmetabolic phenotypeの検討 : 妊娠糖尿病の病態解明をめざして(シンポジウム2:周産期「妊娠とインスリン抵抗性」,第64回日本産科婦人科学会・学術講演会)

宮越敬
日本産科婦人科學會雜誌 64(11), 2265-2278, 2012-11-01
… In the current study, we performed a retrospective cohort study to investigate beta cell function in Japanese pregnant women. … With this background, we conducted preliminary SNP analysis followed by case-control association study in Japanese pregnant women. …
NAID 110009554123

Related Pictures

★リンクテーブル★

リンク元	「症例対照研究」「症例対照法」
拡張検索	「nested case-control study」
関連記事	「study」「control」「case」「stud」「casing」

「症例対照研究」

　　[★]

英: case-control study
同: ケース・コントロール研究
同: 患者対照研究
関: 症例対照法、アトリビュータブル・リスク、コホート研究、分析疫学、マッチング

特徴

	名称	患者対照研究	コホート研究
	時間軸	後向き研究	前向き研究
	調査の方法	既往調査、病歴調査	追跡調査
対象	曝露情報の信頼性	患者の過去の記録やカルテに頼るため信頼性は低い	現時点での曝露状況が判明しているので信頼性は高い
対象	偏りバイアス	抽出の段階で、既に患者、対照群ともに偏りが発生している場合が多い	母集団から、要因の有無別に対照群が抽出されるため、偏りは小さい
対象	まれな要因	評価不能	評価可能
調査	観察期間	なし	長期
調査	費用労力	患者と対照のみを観察するので、費用・労力が少ない	大きな集団を長期に追跡しなければならないので、費用・労力が多い
疾患	対照疾患	単一	複数
疾患	診断の正確性	正確性が高い	正確性が低い →診断基準が必要
疾患	まれな疾患	可能	困難
解析	罹患率	計算不可	算出可能
解析	相対危険度	近似値の算出	算出可能
解析	寄与危険度	計算不可	算出可能