Fact check: What are the most reliable studies on average penis size and their methodologies?

1. Summary of the results

The analyses provided offer insights into the average penis size and its measurement methodologies ^[1]. A systematic review and meta-analysis found that penis size varies significantly across geographical regions, with the largest stretched penile size and largest flaccid length and circumference found in men living in the Americas ^[1]. Another study examined the test-retest reliability of measurement of the erect penis using paper strips in a sample of gay men, finding a moderately low reliability ^[2]. Additionally, a systematic review and meta-analysis investigated the trend of worldwide penile length over time, finding that the average erect penile length has increased over the past three decades across the world ^[3]. Other studies focused on the impact of measuring penile girth and length in the erect state on reassuring individuals with small penis anxiety (SPA) ^[4], and assessed stretched, erect, and flaccid penis length as well as circumference according to geographic WHO regions ^[1]. Some analyses did not provide direct information related to the average penis size or its measurement, but rather listed highly cited articles related to urology ^[5].

2. Missing context/alternative viewpoints

Some key points to consider are the variability in penis size within subjects over time, which may affect the reliability of measurement methods ^[2]. Furthermore, the cause of the increase in average erect penile length over the past three decades remains uncertain ^[3]. The analyses also highlight the importance of considering geographic WHO regions when assessing penis size ^[1]. Additionally, the impact of measuring penile girth and length in the erect state on reassuring individuals with SPA is a crucial aspect to consider ^[4]. Alternative viewpoints may include the potential biases in measurement methods, such as the use of paper strips, which may not be the most reliable method ^[2]. It is also essential to consider the limited generalizability of some studies, such as the one focusing on gay men ^[2].

3. Potential misinformation/bias in the original statement

The original statement asks for the most reliable studies on average penis size and their methodologies, but does not specify any particular population or geographic region ^[1]. This lack of specificity may lead to misinformation or misinterpretation of the results, as penis size varies significantly across geographical regions ^[1]. The statement also does not consider the potential biases in measurement methods, which may affect the reliability of the results ^[2]. The analyses suggest that researchers and healthcare professionals may benefit from considering these factors when assessing penis size and developing measurement methodologies ^{[1] [4]}. Additionally, individuals with small penis anxiety may benefit from being reassured about their penis size, particularly when measured in the erect state ^[4]. Overall, the original statement may benefit from a more nuanced and specific approach to understanding average penis size and its measurement methodologies ^{[1] [2] [4]}.