This study investigated whether phonetic complexity affected stuttering rate in Jordanian Arabic speakers. The authors reported factors that most affected fluency in Jordanian Arabic were place of articulation, manner of articulation, word length, word shape and consonant length.
Al-Tamini, Feda, Khamaiseh, Zaidan, and Howell, Peter. (2013). Phonetic complexity and stuttering in Arabic. Clinical Linguistics & Phonetics. doi:10.3109/02699206.2013.823242