Standardization of clinical assessment and sample collection across All PERCH study sites by Crawley, J, Prosperi, C, Baggett, HC, Brooks, WA, Knoll, M, Hammitt, LL, Howie, SRC, Kotloff, KL, Levine, OS, Madhi, SA, Murdoch, DR, O'Brien, KL, Thea, DM, Awori, JO, Bunthi, C, DeLuca, AN, Driscoll, AJ, Ebruke, BE, Goswami, D, Hidgon, MM, Karron, RA, Kazungu, S, Kourouma, N, Mackenzie, G, Moore, DP, Mudau, A, Mwale, M, Nahar, K, Park, DE, Piralam, B, Seidenberg, P, Sylla, M, Feikin, DR, Scott, JAG