Latar Belakang : Length of stay (LOS) atau ideal time merupakan salah satu indikator penilaian key performance indicator (KPI) patient experience untuk menilai pelayanan IGD. Pencapaian LOS di IGD Mayapada Hospital Bogor baru tercapai 91% di bulan September dari target 100% dengan angka variasi waktu pelayanan yang cukup tinggi.
Metodologi : Penelitian ini menggunakan desain penelitian operational research dengan menggabungkan metode penelitian kuantitatif dan kualitatif (mix methode) dan teknik stratified random sampling untuk metode pengambilan sampel dengan jumlah sebanyak 240 pasien IGD. Penentuan sampel menggunakan rumus Slovin.
Hasil Pembahasan : Pada penelitian ini ditemukan waste waiting sebagai penyebab masalah berdasarkan analisa pareto adalah pada kegiatan menunggu hasil laboratorium sebesar 28% (00:36:20), menunggu hasil radiologi sebesar 21% (00:27:38), persiapan obat, alkes dan oplos obat sebesar 19% (00:24:42) dan menunggu keputusan rawat inap sebesar 23% (00:30:11) dengan total keseluruhan sebesar 91%. Intervensi dengan implementasi lean six sigma yang dilakukan mampu menurunkan angka lead time sebesar (↓ 27,7%) dari 3 jam 59 menit 20 detik menjadi 2 jam 53 menit 2 detik dengan menghilangkan kegiatan non value added sebesar (↓ 37%) dari 2 jam 7 menit 4 detik menjadi 1 jam 20 menit 23 detik. Pada fase kontrol LOS pasien IGD menunjukan penurunan angka lead time sebesar 18% yaitu 2 jam 21 menit 23 detik dan penurunan kegiatan non value added menjadi 51 menit 7 detik
Kesimpulan : Intervensi lean six sigma dengan menggunakan tools standardize work, heijunka, 5S dan brainstorming terbukti mampu menurunkan waktu length of stay pelayanan pasien IGD.

Background                : Length of stay (LOS) or ideal time, is one of the key performance indicators (KPIs) used to assess patient experience in emergency department (ED) services. LOS achievement in the ED reached only 91% of the target 100% in September at Mayapada Hospital Bogor, with a high variation in service time. Methodology                : This study uses an operational research design, combining quantitative and qualitative research methods (mixed methods), and employs stratified random sampling techniques. The sampel size consisted of 240 ED patients, determined using the Slovin formula. Results and Discussion: In this study, the identified cause of the problem based on pareto analysis was waste due to waiting, with the following breakdown : waiting for laboratory results accounted for 28% (00:36:20), waiting for radiology results 21% (00:27:38), preparation of medications, medical devices, and drug mixing 19% (00:24:42), and waiting for inpatient admission decisions 23% (00:30:11), comprising a total of 91%. The intervention through the implementation of lean six sigma successfully reduced lead time by 27.7%, from 3 hours 59 minutes 20 seconds to 2 hours 53 minutes 2 seconds, by eliminating non–value-added activities by 37%, from 2 hours 7 minutes 4 seconds to 1 hour 20 minutes 23 seconds. In the control phase, the Emergency Department patient length of stay (LOS) showed a lead time reduction of 18%, equivalent to 2 hours, 21 minutes, and 23 seconds, and a decrease in non-value-added activities to 51 minutes and 7 seconds. During the control phase, the length of stay (LOS) for emergency department (ED) patients showed a further lead time reduction of 18%, reaching 2 hours 21 minutes 23 seconds, with a reduction in non–value-added activities to 51 minutes 7 seconds. Conclusion                : Lean Six Sigma interventions, utilizing tools such as standardized work, heijunka, 5S, and brainstorming, effectively reduced the length of stay for ED patients.