Do randomized clinical trials with inadequate blinding report enhanced placebo effects for intervention groups and nocebo effects for placebo groups?

Systematic Reviews

Volumn 3, Issue 1, 2014, Pages

  Feys, Frederik ^a   Bekkering, Geertruida E ^b,c   Singh, Kavita ^d   Devroey, Dirk ^a  

^a VRIJE UNIVERSITEIT BRUSSEL   (Belgium)

^b Belgian Center for Evidence Based Medicine   (Belgium)

^c BeSyRe Bekkering Systematic Reviews   (Belgium)

^d OTTAWA HOSPITAL RESEARCH INSTITUTE   (Canada)

Author keywords

Bias; Double blind; Expectancy; Nocebo; Phosphodiesterase 5 inhibitor; Placebo; Randomized controlled trial; Treatment efficacy

Indexed keywords

PHOSPHODIESTERASE V INHIBITOR; PLACEBO;

ARTICLE; BIBLIOGRAPHIC DATABASE; ERECTILE DYSFUNCTION; HUMAN; INFORMATION PROCESSING; META ANALYSIS (TOPIC); METHODOLOGY; NOCEBO EFFECT; OUTCOME ASSESSMENT; PLACEBO EFFECT; PRIORITY JOURNAL; RANDOMIZED CONTROLLED TRIAL; RANDOMIZED CONTROLLED TRIAL (TOPIC); SCIENTIFIC LITERATURE; SCORING SYSTEM; SYSTEMATIC REVIEW (TOPIC); TREATMENT OUTCOME; DOUBLE BLIND PROCEDURE; MALE; RANDOMIZATION; STANDARD;

DOUBLE-BLIND METHOD; ERECTILE DYSFUNCTION; HUMANS; MALE; NOCEBO EFFECT; PHOSPHODIESTERASE 5 INHIBITORS; PLACEBO EFFECT; PLACEBOS; RANDOM ALLOCATION; RANDOMIZED CONTROLLED TRIALS AS TOPIC;

EID: 84907276003     PISSN: None     EISSN: 20464053     Source Type: Journal    
DOI: 10.1186/2046-4053-3-14     Document Type: Article

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