What is the average penis length in erect state?

First of all, i would like to say, almost all internet articles over-estimate the average size of the penis length in erect state. Averages and penis sizes are useless if the datasource does not provide the detailed methodology of measurement hat has been used to provide figures.

The results of the Kinsey institute penis size study are bogus:

Many times, the methodology description is either missing or partial. Many penis length studies are useless and shouldn’t be considered as serious data. For instance, The 1979 average penis length given by the Kinsey institute report shouldn’t be taken into account. The said research data have been self-reported by participants. It means each man could provided measurement that were not real during the research. Thus, data cannot be accurate.

The Wessells penis study is vague:

According to the Wessells study published in the 1996 US journal of Urology, the US average erect penis length is equal to 12.9 cm (5.09 inches) non-bone pressed.  Unfortunately, The study abstract didn’t explain how the tape has been positioned to measure penises. Penis length can be tremendously different whether the tape is placed on the penis or next to the penis. In this circumstances, how can we compare a real-life penis to the Wessells study if we are not 100% sure of the measurement methodology?

The lifestyles condom study is partial:

The lifestyles condom average penis size is equal to 14.9 cm. Knowing that lifestyles condom measured students we can imagine that the lifestyle condom age range was from 20 to 30 years old. Methodology, table of records and penis length distribution charts have never been published by the lifestyle condom manufacturer Ansell. Every explanation seen on the internet are only speculations. Except the average size of the penis in erect state extracted from the Ansell company, everything you find on the internet regarding the said study methodology has no reference.

The Tel aviv Sourasky study:

The tel aviv Sourasky study measured 55 men aged from 21 to 78 years old. The study details the measurement methodology as follow: All penile measurements and evaluations were performed by the same investigator (JC), thereby eliminating inter-observer variations. Only patients who achieved full erection (and without penile curvature) were included in the ®nal analysis. The study was conducted in a dimly lit private room, and the patient was in supine position. Penile length was measured by a caliper. While measuring penile length at the dorsal aspect, the caliper was pushed into the pubic bone in order to eliminate the effect of the pubic fat pad. Penile length was measured dorsally from the pubo-penile angle to the meatus, and ventrally from the penoscrotal junction to the meatus side. Circumference was measured by an ordinary `tumo-meter’ at the penile base and at the corona. Penile dimensions were measured in a ¯accid state and during axial stretching in which the glans was gently stretched until the patient expressed discomfort.
Using this methodology the israeli scientists found the average penis length was equal to 13.6 cm bone pressed. For your information, the participants age average was 47 years old. We know that older men are overweight and when it happens, they “lose” erect penis length. In other words, the average penis size would be higher if participants were younger.
In order to get a good overview of the average penis size, we would need several new penis size studies detailing their erect penis size measurements methodology. Today, we have still too few reliable penis size studies to know what the real average erect penis size is. We basically need everything. We need studies of penis size per ethnicity. We need  studies of penis size per age. We need studies of penis size in different countries.